Let's compare them with the slope and y-intercept of the line of best fit! In the previous exercise, we drew the following line of best fit.
The y-intercept is the y-value when x=0. We can find it on the graph.
We can see that the y-intercept is equal to about 25. Now to find the slope, we need to choose any two points on the line.
The first point has coordinates x_1= 0 and y_1= 24. The second point has coordinates x_2= 15 and y_2= 20. Let's substitute these values into the slope formula!
We found that the slope of our line of best fit is equal to about -0.3 and that the y-intercept is equal to about 25. Let's compare that with the slopes and y-intercepts of the given equations.
Option
Equation
Slope
Y-intercept
A
y= 0.3x+ 25
0.3
25
B
y= 0.3x -25
0.3
-25
C
y= -0.3x+ 25
-0.3
25
D
y= -0.3x -25
-0.3
-25
Notice that only equation C has the same slope and y-intercept as our line of best fit. Therefore, option C is correct.
