Persamaan garis yang melalui titik A (-2, -5) dan B (3,-7) adalah...

titik A (-2, -5)
x1 = -2
y1 = -5
 titik B (3, -7)
x2 = 3
y2 = -7

subtitusi titik A (-2, -5) dan titik B (3, -7) ke persamaan
y-y1 / y2-y1 = x-x1 / x2-x1
y-(-5) / -7-(-5) = x-(-2) / -5-3
y+5 /-2 =x+2 /-8
(y+5)*(-8)= (x+2)(-2)
-8y - 40 = -2x - 4
-8y  = -2x -4 +40
-8y = -2x+36

a = (-2 , -5)
x1 , y1
b = (3 , -7)
x2 , y2

y2-y1 / x2-x1
= -7-(-5) / 3-(-2)
= -7+ 5 / 3+2
= -2 / 3

y-y1 = m(x-x1)
y-(-5) = -2/3 (x-(-2))
y+5 = -2/3 (x+2)
y+5 = -2/3x + 4/3
y = -2/3x + -11/3
__________ *3
y = -2x + 11