Find $y$ if the point $(-6,y)$ is on the line that passes through $(-1,7)$ and $(3,-2)$.
slope = 9/-4
y = -9/4 x + a
7 = 9/4 + a
a = 7 - 9/4 = 19/4
$y = \frac{-9}{4} x + \frac{19}{4}$
$y = 13.5 + 4.75$
$y = 18.25$
slope = 9/-4
y = -9/4 x + a
7 = 9/4 + a
a = 7 - 9/4 = 19/4
$y = \frac{-9}{4} x + \frac{19}{4}$
$y = 13.5 + 4.75$
$y = 18.25$