Answer:
y = -4x + 1
Step-by-step explanation:
The line passes through points (-5,21) and (-4,15)
Slope(m) = change in y ÷ change in x
m = [tex]\frac{-15 - 21}{4 - -5}[/tex]
m = [tex]\frac{-15 - 21}{4 + 5}[/tex] = -36/9 = -4
Taking another point (x,y) on the line and comparing it with point (4,-15):
-4 = [tex]\frac{y + 15}{x - 4}[/tex]
Cross multiplying gives:
y + 15 = -4x + 16
y = -4x + 1