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A trend line is a line that approximates the relationship between the variables or data sets of a scatter plot. Begin by sketching it!
Use the equation of the trend line.
Use the equation of the trend line.
Use the equation of the trend line and find the expenditure. Compare the value that you found and the given value.
Example Solution:
About $2506
About $5610
See solution.
Let x and y represent Per Capita Revenue and Per Capita Expenditure, respectively.
| State | Per Capita Revenue ($) | Per Capita Expenditure ($) |
|---|---|---|
| Arizona | 4144 | 3789 |
| Georgia | 3904 | 3834 |
| Maryland | 5109 | 4557 |
| Mississippi | 5292 | 4871 |
| New Mexico | 6205 | 5793 |
| Nevada | 4345 | 3723 |
| New York | 7081 | 6891 |
| Texas | 4030 | 3442 |
| Utah | 5439 | 4459 |
Let's plot the points on the coordinate plane.
A trend line is a line that approximates the relationship between the variables or data sets of a scatter plot. Remember that the trend line may vary for each person based where they decided to draw their line of fit. Let's sketch it!
To write the equation of the line, we should first determine its slope. Therefore, we will choose two points on the line. Looking at the graph, we can choose the points (4000,3516) and (6400,5940). Let's use the Slope Formula!
Substitute ( 4000,3516) & ( 6400,5940)
Subtract terms
Calculate quotient
Now that we know the slope of the line and a point that it passes through, we can write the equation in the point-slope form. Let (6400,5940) be our reference point. y-y_1=m(x-x_1) ⇕ [0.5em] y-5940=1.01(x-6400) By isolating y, we can rewrite the equation in slope-intercept form to make it a bit easier to understand.
By substituting 3000 for x into the equation of the trend line, we can find the expenditure of the state. Let's do it!
x= 3000
Multiply
Subtract term
The state would spend about $2506 per capita.
We have been told that Ohio spent $5142 per capita during the year. Let's substitute 5142 for y into the equation and solve it for x to find Ohio's revenue.
y= 5142
LHS+524=RHS+524
.LHS /1.01.=.RHS /1.01.
Rearrange equation
Round to 1 decimal place(s)
Therefore, its revenue is about $5610.
To decide whether the revenue and expenditure of New Jersey follows the trend, we will substitute 5825 for x into the equation and solve it for y.
x= 5825
Multiply
Subtract term
Since the value that we found is close to $5348, the information follows the trend.