Answer:
Step-by-step explanation:
Here is your x/y table, a bit more organized:
x | 3 5 7
y | -2 -26 -50
The rate of change is the same thing as the slope. If the slope between coordinates 1 and 2 is the same as the slope between coordinates 2 and 3, we have a linear function in the form y = mx + b, where m is the slope and b is the y-intercept. We will have to solve for b if we want to use this form. Or we could use the point-slope form and not have to solve for b. Let's do that. But first things first. The slope:
Between the first 2 coordinates (3, -2) and (5, -26):
[tex]m=\frac{-26-(-2)}{5-3}=\frac{-24}{2}=-12[/tex]
Between coordinates 2 and 3 which are (5, -26) and (7, -50):
[tex]m=\frac{-50-(-26)}{7-5} =\frac{-24}{2}=-12[/tex]
The slopes are the same, so this in fact a linear function with m = -12. But that's all we have, so let's use the point-slope form of a line to write the equation:
[tex]y-y_1=m(x-x_1)[/tex] where [tex]x_1[/tex] and [tex]y_1[/tex] are coordinates found in the table. Plugging in the first coordinate along with the slope of -12:
[tex]y-(-2)=-12(x-3)[/tex] and
y + 2 = -12x + 36 and
y = -12x + 36 - 2 so the equation for the line in slope-intercept form is
y = -12x + 34
Regardless of which coordinate point you choose as your x1 and y1, I promise you that you will still get the same equation for the line!
