.Identify the sampling technique used for the following samples. (1 mark each) i) After a hurricane, a disaster area is divided into 100 equal grids. Twenty randomly selected households were interviewed from every grid to help focus relief efforts on what residents require the most. ii) Questioning students as they leave the university’s computer lab, a researcher asks 250 students about their study habits. iii) If a researcher wishing to draw a sample from sequentially numbered invoices uses a random starting point, then draws every 50th invoice.
Answers
Stratified sampling is a probability sampling technique in which the population is divided into groups or strata, and then a random sample is selected from each group.
In this case, the population is the disaster area, and the strata are the 100 equal grids.
i) The sampling technique used in this case is cluster sampling. This method allows for a more efficient data collection process by grouping households within each grid,
The disaster area is divided into 100 equal grids, and 20 households are randomly selected from each grid. This method allows for a more efficient data collection process by grouping households within each grid, which helps in targeting relief efforts based on the specific needs of each grid.
ii) The sampling technique used in this case is convenience sampling. The researcher questions students as they leave the university's computer lab,
which means the sample consists of students who are readily available and accessible at that particular location and time. Convenience sampling is convenient and easy to implement, but it may introduce bias since the sample may not be representative of the entire student population.
iii) The sampling technique used in this case is systematic sampling. The researcher starts at a random starting point and then selects every 50th invoice. Systematic sampling ensures that the sample is evenly spread across the population,
as it selects every nth item from a sequential list. However, it is important to ensure that there is no underlying pattern or periodicity in the list that could influence the sample selection process and introduce bias.
To know more about area click here
brainly.com/question/13194650
#SPJ11
Related Questions
What is the area of the parallelogram?
Answers
Answer:
A=112 in. squared
Step-by-step explanation:
A=bxh=14·8=112
Step-by-step explanation: In this problem, we're asked to find the area of the parallelogram shown. Remember that a parallelogram is a quadrilateral with two pairs of parallel sides.
The formula for the area of a parallelogram is bh.
Since the base of the parallelogram is 14 inches and the height of the parallelogram is 8 inches, we can plug this information into the formula
to get (14 in.)(8 in.) which equals 112 in.².
Find the surface area of the solid formed by the net.
Answers
Answer:
Step-by-step explanation:
m
Answer:
535.44 cm squared
Step-by-step explanation:
f(x) = 4x² + 5x - 3
g(x) = 4x³
3x² + 5
Find (f+g)(x).
Answers
Answer:
\(4x^3+7x^2+5x+2\)
Step-by-step explanation:
Given:
\(f(x)=4x^2+5x-3\)
\(g(x)=4x^3+3x^2+5\)
\(\begin{aligned}\implies (f+g)(x)=f(x)+g(x) & = (4x^2+5x-3) + (4x^3+3x^2+5) \\& = 4x^2+5x-3+4x^3+3x^2+5 \\& = 4x^3+4x^2+3x^2+5x-3+5 \\& = 4x^3+7x^2+5x+2 \\\end{aligned}\)
answer this question for me.
Answers
Answer: 5.7 (rounded)
Step-by-step explanation: The formula to find the diagonal of a square is \(\sqrt{2\) * a, where a is a side length on the square. Since we are solving for half of a diagonal, we use this formula and divide our result by two. We start by multiplying root 2 by 8 and we get 11.31371, next we divide by two and we get 5.656855 which is 5.7 when rounded.
PLEASE HELP ME
If m<2=8x-19,and m<4=5x+5, what is the m<4?
Answers
Answer:
45
Step-by-step explanation:
Line C is a transversal as it crosses both a and b which appear to be parallel.
Using this, angle 2 and angle 4 are congruent.
This means :
8x-19 = 5x+5
Solving this gives us x = 8.
Now if we plug 8 back into the formula for m<4, we'd get 5(8)+5 or 45.
I NEED AN ANSWER ASAP PLEASE
Answers
Step-by-step explanation:
the correct answer is option a 6a-7
52÷25
What is the answer :)
Answers
Answer:
2.08 this is answer
Bob earned $2100. He spent 1/5 of his money on rent and 1/3 of it on food. How much money did he have left?
Answers
Answer:
$980
Step-by-step explanation:
Step 1: Find \(\frac{1}{5}\) of 2100 = 420
\(\frac{1}{5}\times \:2100\)Convert 2100 to a fraction: \(\:2100=\frac{2100}{1}\)\(=\frac{1}{5}\times \frac{2100}{1}\)Cross Divide\(2100 \div 5 = 420\)Step 2: Find \(\frac{1}{3}\) of 2100 = 700
\(\frac{1}{3}\times \:2100\)Convert 2100 to a fraction: \(\:2100=\frac{2100}{1}\)\(=\frac{1}{3}\times \frac{2100}{1}\)Cross Divide\(2100 \div 3 = 700\)Step 3: Add both results together
\(420 + 700 = 1120\)
Step 4: Subtract the result from how much Bob earns ($2,100)
\(2100 - 1120 = 980\)
Bob has $960 left
Jessica and Barry squeezed oranges for juice. Jessica squeezed 23 5 cups of juice. Barry made 1 4 cup less than Jessica. Barry estimated that Jessica squeezed about 21 2 cups of juice. Which is the best estimate for the amount of juice Barry made? 2 1/4 cups How much juice did Barry actually make? 2 and three-fifths minus one-fourth = StartFraction 13 over 5 EndFraction minus one-fourth = StartFraction 52 over 20 EndFraction minus StartFraction 5 over 20 EndFraction
Answers
Answer:
1. 2 1/4 cups
2. 2 7/20 cups
Answer:
2 1/4 and 2 7/20
Step-by-step explanation:
(4x-5)+(2x+1) CAn anyone help with this
Answers
Answer:
6x -4
Step-by-step explanation:
(4x-5)+(2x+1)
Combine like terms
4x+2x -5 +1
6x -4
Solve by elimination 8x-9y =19
4x-y = 7
Answers
Answer:
Point form:
(11/7, -5/7)
Equation form:
x = 11/7, y = -5/7
Which input value produces the same output value for
the two functions?
O x= -12
O x= -9
O x= -6
O X=-3
HELP PLEASE
Answers
Answer
-6
Step-by-step explanation:
Took test
A child rolls a ball on a level floor 3.5m to another child. If the ball makes 15.0 revolutions, what is its diameter?
Answers
The diameter of the ball is approximately 16.67 meters.
To find the diameter of the ball, we can use the relationship between the distance traveled and the number of revolutions.
The circumference of a circle is given by the formula C = πd, where C is the circumference and d is the diameter.
Given that the ball rolls a distance of 3.5 meters and makes 15.0 revolutions, we can calculate the circumference of the path it travels:
C = 3.5 m * 15.0 = 52.5 m
Since each revolution covers the circumference of the ball, we have C = πd. Plugging in the known value for C, we can solve for the diameter (d):
52.5 m = πd
Dividing both sides of the equation by π, we get:
d = 52.5 m / π
Using a calculator, we can evaluate this expression:
d ≈ 16.67 meters
Learn more about circles and circumferences here:
https://brainly.com/question/17130827
#SPJ11
Which graph shows the line y = x + 1?
Answers
Here is a picture of a bobcat anyway
The linear function graphed below represents Brenda’s monthly cell phone bill based on the number of hours she uses. What is her hourly rate? A graph titled Brenda's Monthly Cell Phone Bill has hours used on the x-axis and cell phone bill (dollars) on the y-axis. Points plotted are (1, 27), (2, 39), and (3, 51). $12 per hour $15 per hour $27 per hour $39 per hour
Answers
Answer:
$12 per hour
Step-by-step explanation:
In order to find her hourly rate we have to find the amount of dollars billed per hour. To do this we can use this expression: \(\frac{y2 - y1}{x2 - x1}\)
Let's use the points (1, 27) and (2, 39) in the expression:
\(\frac{39 - 27}{2 -1}\)
Now let's simplify the expression:
39 - 27 = 12
2 - 1 = 1
The expression simplifies to 12/1, or 12. This means that Brenda is billed $12 every hour she uses her phone.
I hope this helps :)
Answer:
12$ per hour!
Step-by-step explanation:
Which table graph represents the equation y=2x?
Answers
Answer:
From the two graphs, I can see in the picture, I can tell that the left graph represents y=2x because the y-intercept is 0 and the slope is 2 because the line goes up two and over one (2/1) or just 2.
Step-by-step explanation:
Hope this helps
The graph below shows a company’s profit f(x) in dollars depending on the price of pens x, in dollars, sold by the company What do the x-intercepts and maximum value of the graph represent? What are the intervals where the function is increasing and decreasing and what do they represent about the sale and profit? What is an aproxímate average rate of change of the graph from x=3 to x=5 and what does this rate represent?
Answers
Solution:
Given:
\(\begin{gathered} f(x)=profits \\ x=price\text{ of pens} \end{gathered}\)From the graph, the x-intercept exists at (0,0) and (6,0).
The maximum value is (3,120).
The x-intercept represents the break-even points. The company was not in profit or loss when no pen was sold and when 6 pens were sold, the profit was $0 at these two points.
The maximum value of the graph represents the maximum profit made by the company. The company made a maximum profit of $120 when 3 pens were sold.
The interval where the function is increasing is from negative infinity to x = 3. This shows that the more pen sold, the higher the profit made.
The interval where the function is decreasing is from x = 3 to positive infinity. This shows that the less pen sold, the lower the profit made.
The approximate average rate of change of the graph from x = 3 to x = 5 is;
\(\begin{gathered} ARC=\frac{f(x_2)-f(x_1)}{x_2-x_1} \\ where: \\ x_1=3 \\ x_2=5 \\ f(x_1)=120 \\ f(x_2)=60 \\ \\ Hence, \\ ARC=\frac{60-120}{5-3} \\ ARC=\frac{-60}{2} \\ ARC=-30 \end{gathered}\)The rate represents a decrease of $30 for every pen sold across the decreasing interval.
Jake is making bracelets to give to his sisters. He uses 4 rainbow charms and 8 white star charms for his younger sister's bracelet. He makes his older sister's bracelet a little bigger, so he uses 5 rainbow charms and 10 white star charms. Does Jake use the same ratio of rainbow charms to white star charms in both bracelets?
Answers
Answer: Yes.
Step-by-step explanation: 4:8 simplifies to 1:2, since he used half as many rainbow charms as he did white stars. 5:10 also simplifies to 1:2. If they both have half as many rainbow charms as white, then both of his sister’s bracelets keep the same ratio.
Check if the equation 456x = 32 (mod 1144) has integer
solutions, why? If yes, find all integer solutions.
Answers
The solution is x = 114l + 23 where l is an integer.
Given equation is 456x = 32 (mod 1144)a
Checking if the equation 456x = 32 (mod 1144) has integer solutions
For the equation ax = b (mod n) to have a solution, it is necessary and sufficient that d = gcd(a,n) divide b.
Now, gcd(456, 1144) = 456So, 456 divides 32.So, the equation 456x = 32 (mod 1144) has integer solutions.
To find all integer solutions:1144 = 2 * 2 * 2 * 11 * 13 , We have 456x ≡ 32 (mod 1144)As gcd(456, 1144) = 456,
Let us divide both sides of the equation by 456x ≡ 32 (mod 1144) 456x/456 ≡ 32/456 (mod 1144/456)
x ≡ 8 (mod 2*2*11*13/456) x ≡ 8 (mod 13)
Since 2, 11 are not coprime to 456, we have to solve other congruences separately , x ≡ 8 (mod 13) and x ≡ ? (mod 2), x ≡ ? (mod 11)
Let us solve x ≡ 8 (mod 13)x = 13k + 8
Since x ≡ 8 (mod 13) satisfies the other conditions, we have to only solve for x ≡ ? (mod 2), x ≡ ? (mod 11)
By Chinese remainder theorem, we have to solve for the following 2 congruences separately.x ≡ ? (mod 2), x ≡ ? (mod 11)x ≡ ? (mod 2)If x ≡ 0 (mod 2), then 456x ≡ 0 (mod 2) which is not true.
Therefore, x ≡ 1 (mod 2).x = 2l + 1x ≡ 1 (mod 11)If x = 11m + 1, then 456x = 456(11m + 1) = 5016m + 456 ≡ 0 (mod 11)If m = 2, then x = 23 satisfies the given congruences.
Hence the solution isx = 114l + 23 where l is an integer
#SPJ11
The box plots display measures from data collected when 20 people were asked about their wait time at a drive-thru restaurant window.
A horizontal line starting at 0, with tick marks every one-half unit up to 32. The line is labeled Wait Time In Minutes. The box extends from 8.5 to 15.5 on the number line. A line in the box is at 12. The lines outside the box end at 3 and 27. The graph is titled Super Fast Food.
A horizontal line starting at 0, with tick marks every one-half unit up to 32. The line is labeled Wait Time In Minutes. The box extends from 9.5 to 24 on the number line. A line in the box is at 15.5. The lines outside the box end at 2 and 30. The graph is titled Burger Quick.
Which drive-thru typically has more wait time, and why?
Burger Quick, because it has a larger median
Burger Quick, because it has a larger mean
Super Fast Food, because it has a larger median
Super Fast Food, because it has a larger mean
Question 2
The box plot represents the number of tickets sold for a school dance.
A horizontal line labeled Number of Tickets sold that starts at 8, with tick marks every one unit up to 30. The graph is titled Tickets Sold for A Dance. The box extends from 17 to 21 on the number line. A line in the box is at 19. The lines outside the box end at 10 and 27.
Which of the following is the appropriate measure of center for the data, and what is its value?
The mean is the best measure of center, and it equals 19.
The median is the best measure of center, and it equals 4.
The median is the best measure of center, and it equals 19.
The mean is the best measure of center, and it equals 4.
Question 3
A charity needs to report its typical donations received. The following is a list of the donations from one week. A histogram is provided to display the data.
5, 5, 6, 8, 10, 15, 18, 20, 20, 20, 20, 20, 20
A graph titled Donations to Charity in Dollars. The x-axis is labeled 1 to 5, 6 to 10, 11 to 15, and 16 to 20. The y-axis is labeled Frequency. There is a shaded bar up to 2 above 1 to 5, up to 3 above 6 to 10, up to 1 above 11 to 15, and up to 7 above 16 to 20.
Which measure of variability should the charity use to accurately represent the data? Explain your answer.
The range of 13 is the most accurate to use, since the data is skewed.
The IQR of 13 is the most accurate to use, since the data is skewed.
The range of 20 is the most accurate to use to show that they have plenty of money.
The IQR of 20 is the most accurate to use to show that they need more money.
Question 4
The circle graph describes the distribution of preferred transportation methods from a sample of 400 randomly selected San Francisco residents.
circle graph titled San Francisco Residents' Transportation with five sections labeled walk 40 percent, bicycle 8 percent, streetcar 15 percent, bus 10 percent, and cable car 27 percent
Which of the following conclusions can we draw from the circle graph?
Together, Streetcar and Cable Car are the preferred transportation for 168 residents.
Together, Walk and Streetcar are the preferred transportation for 55 residents.
Bus is the preferred transportation for 45 residents.
Bicycle is the preferred transportation for 50 residents.
Question 5
The line plot displays the number of roses purchased per day at a grocery store.
A horizontal line starting at 1 with tick marks every one unit up to 10. The line is labeled Number of Rose Bouquets, and the graph is titled Roses Purchased Per Day. There is one dot above 1 and 2. There are two dots above 8. There are three dots above 6, 7, and 9.
Which of the following is the best measure of variability for the data, and what is its value?
The range is the best measure of variability, and it equals 8.
The range is the best measure of variability, and it equals 2.5.
The IQR is the best measure of variability, and it equals 8.
The IQR is the best measure of variability, and it equals 2.5.
Question 7
At a recent baseball game of 5,000 in attendance, 150 people were asked what they prefer on a hot dog. The results are shown.
Ketchup Mustard Chili
63 27 60
Based on the data in this sample, how many of the people in attendance would prefer mustard on a hot dog?
900
2,000
2,100
4,000
Question 8
The number of milligrams of Vitamin C from 100 different gummy vitamins sold in the world was collected.
Which graphical representation would be most appropriate for the data, and why?
Box plot, because the median can easily be determined from the large set of data
Stem-and-leaf plot, because you can see the shape of the data
Histogram, because it shows each individual data point
Bar chart, because the data is categorical
Answers
Burger Quick, because it has a larger median.
How to explain the informationBurger Quick typically has more wait time because it has a larger range (30-2=28) compared to Super Fast Food (27-3=24) and also has a larger interquartile range (IQR) (24-9.5=14.5) compared to Super Fast Food (15.5-8.5=7), indicating more variability in the wait times. The fact that Burger Quick's median (15.5) is larger than Super Fast Food's median (12) reinforces this conclusion.
Therefore, the correct answer is: Burger Quick, because it has a larger median.
Answer 2: The appropriate measure of center for this data is the median, which is represented by the line in the box at 19. This is because the data is skewed, with a longer tail to the right, and the median is less sensitive to extreme values compared to the mean. Therefore, the correct answer is: The median is the best measure of center, and it equals 19.
Answer 3: The measure of variability that the charity should use to accurately represent the data is the IQR (Interquartile Range), which is the range of the middle 50% of the data. The reason for this is that the data is skewed to the right, with many values concentrated in the upper range of the data, and the IQR is less sensitive to outliers compared to the range.
The IQR for this data is 20-10=10, which represents the spread of the middle 50% of the data. Therefore, the correct answer is: The IQR of 20 is the most accurate to use, since the data is skewed.
Learn more about median on
https://brainly.com/question/26177250
#SPJ1
A conference room holds 25 people in medium weight office dress. The total heat gain to the space has been determined to be 52,500Btu/hr of which 42,000Btu/hr is sensible heat transfer. The outdoor air has a temperature of 86 ∘
F and a relative humidity of 60 percent. 3. Assuming that the air entering the space is 15 ∘
F less than the temperature of the space, determine the quantity (volume flow rate) and state (relative humidity) of the air to be supplied to the space.
Answers
The volume flow rate of the air supply required is 533 CFM and the relative humidity of the air supply should be 60% and the dew point temperature of the air supply should be 55.2°F.
The quantity of air required is calculated using the formula:
CFM = Q/(1.08 x ΔT x 1.1) where,
Q = Sensible Heat Load in Btu/hr
ΔT = Temperature Difference between Room Air and Outdoor Air
CFM = Cubic Feet per Minute of Air Supply 1.08 = Specific Heat of Air at Constant Pressure 1.1 = Density of Standard Air at 70°F and 29.92" Hg Absolute.
According to the problem statement,
Q = 42,000 Btu/hr
ΔT = (86 - 15)°F = 71°F
CFM = 42,000/(1.08 x 71 x 1.1)
= 532.9
~ 533 CFM
Thus, we can say that the volume flow rate of the air supply required is 533 CFM and the relative humidity of the air supply should be 60%, and the dew point temperature of the air supply should be 55.2°F.
To know more about the Sensible Heat Load, visit:
brainly.com/question/30779792
#SPJ11
let p be the price of an item. the unit sales of the item are 200 - 5p. what is the correct formula for the revenue generated by the item?
Answers
The correct formula for the revenue generated by the item is Revenue = 200p - 5p^2.
The revenue generated by the item can be calculated by multiplying the price (p) by the unit sales (200 - 5p). Therefore, the correct formula for the revenue generated by the item is:
Revenue = Price x Unit Sales
Revenue = p(200 - 5p)
Revenue = 200p - 5p^2
The revenue generated by the item is a quadratic function of the price (p). To find the maximum revenue, we need to differentiate the function with respect to p and set it equal to zero:
dRevenue/dp = 200 - 10p = 0
10p = 200
p = 20
Therefore, the maximum revenue is generated when the price of the item is $20. Substituting p = 20 in the revenue formula, we get:
Revenue = 200(20) - 5(20^2) = $2000
Hence, the correct formula for the revenue generated by the item is Revenue = 200p - 5p^2, and the maximum revenue is achieved when the price of the item is $20, generating a revenue of $2000.
Know more about revenue here,
https://brainly.com/question/29567732
#SPJ11
What are the side lengths of CB and DB
Answers
The value of CB and DB are 3.25 and 5.2
What are similar triangles?Similar triangles are triangles that have the same shape, but their sizes may vary. All equilateral triangles, squares of any side lengths are examples of similar objects. In other words, if two triangles are similar, then their corresponding angles are congruent and corresponding sides are in equal proportion.
CA = √ 4²+3²
CA = √ 16+9
CA = √ 25
CA = 5
represent DB by x
5/3+x = 4/5
25 = 4(3+x)
3+x = 25/4
3+x = 6.25
x = 6.25 - 3
x = 3.25
represent CB by y
y² = 3.25² + 4²
y²= 10.56+16
y² = 26.56
y = √ 26.56
y = 5.2
learn more about similar triangles from
https://brainly.com/question/14285697
#SPJ1
A caleteria serving line has a coffee urn from which customers serve themselves. Arrivals at the urn follow a Poisson distribution at the fate of three per minute. In serving themselves, customers fak
Answers
In a cafeteria serving line, the arrivals at the coffee urn follow a Poisson distribution with a rate of three customers per minute. The customers serve themselves from the urn.
The Poisson distribution is commonly used to model the number of events occurring in a fixed interval of time or space. In this case, the rate parameter lambda is given as three customers per minute. This means that, on average, three customers arrive at the coffee urn every minute.
Since the customers serve themselves from the urn, their serving behavior can be assumed to be independent of each other. Each customer takes their own time to serve themselves, which may vary depending on their preferences and the availability of the coffee.
The Poisson distribution allows us to calculate the probability of a specific number of customers arriving at the coffee urn within a given time interval. Additionally, it enables us to analyze the expected number of customers arriving during a particular period.
Understanding the arrival pattern and distribution of customers at the coffee urn can help cafeteria staff in managing the availability of coffee, ensuring an adequate supply for customers, and optimizing the serving line to minimize waiting times during peak hours.
Learn more about Poisson distribution here:
https://brainly.com/question/30388228
#SPJ11
2×5÷5-1+(4×8)
Please help me solve
Answers
Answer:
ans is 33
Step-by-step explanation:
2×5÷5-1+32
=10÷5-1+32
=2-1+32
=2+31
=33
Answer:
33
Step-by-step explanation:
Order of operations is PEMDAS (Parentheses, Exponents, Multiplication + Division, Addition + Subtraction)
1. Parentheses: (4x8) = 32
2x5÷5-1+32
2. Exponents: None
3. Multiplication + Division, left to right: 2x5÷5 = 10÷5=2
2-1+32
4. Addition + Subtraction, left to right: 2-1+32 = 1+32 = 33
The radius of a circular pond is 8 meters. Find it's area and circumference. Use 3. 14 as an approximation for pi
Answers
Area = 3.14 x (8)^2
Area = 200.96 meters squared
Circumference = pi x 2r
= 3.14 x 2 x 8
= 50.24 meters
A 2 cm radius ball rests on a table as shown in the figure. Suppose we select the table as the reference plane, the bottom of the ball as its reference point, the y-axis along a vertical line, and the positive direction as pointing upward. What is the y-coordinate of the ball?.
Answers
the center of the ball rests on the table which implies that the y-coordinate of the center of the ball is zero since we have selected the table as the reference plane
the bottom of the ball as its reference point, the y-axis along a vertical line, and the positive direction as pointing upward can be calculated as follows:The y-coordinate of the ball = (y-coordinate of the center of the ball) - (the radius of the ball)As per the given problem, the center of the ball rests on the table which implies that the y-coordinate of the center of the ball is zero since we have selected the table as the reference plane.Hence, the y-coordinate of the ball = 0 - 2= -2Therefore, the y-coordinate of the ball is -2.
learn more about rests here;
https://brainly.com/question/29132935
#SPJ11
If f(x) = x4 − x3 + x2 and g(x) = −x2, where x ≠ 0, what is (f ⁄g)(x)? m
Answers
Answer:x − x^{2} − 1.
Step-by-step explanation:
.
May I please receive help?
Answers
Answer:
(32)2
1024
(28) 2
784
1024-784= 240
I think nearest 10 can 256 or 225 then find square
If y varies directly as x andx = 12 when y = 24, what is x when y = 8? (I just need to know the rate of change, y-intercept, x-intercept, what m & b are, & what the equation is in slope-intercept form.)
Answers
If y varies directly as x and x = 12 when y = 24, what is x when y = 8.?
So, y = c * x
where c is constant
x = 12 when y = 24
so,
24 = c * 12
c = 24/12 = 2
so,
y = 2x
Now, need to find x when y = 8
so,
8 = 2x
x = 8/2 = 4
===============================================================
From the graph:
y-intercept = 3 , it is the value of y when x = 0
the general form of the line: y = mx + b
where b is y-intercept
So, y = mx + 3
to find m, choose point like (2 , 2) and substitute with it
so, y = 2 when x =2
2 = 2m + 3
2m = -1
m = -1/2 = -0.5
so, y = -0.5x + 3
so, to find x-intercept is the value of x when y = 0
so, 0 = -0.5x + 3
0.5x = 3
x = 3/0.5 = 6
m is the slope = -0.5
b is y-intrcept = 3