The point a(-3,5) and the point b(1,-15) lie on the line l. find the equation of the line l.

(-3,5)(1,-15)
slope = (-15 - 5) / (1 - (-3) = -20/4 = -5

y = mx + b
slope(m) = -5
use either of ur points...(-3,5)...x = -3 and y = 5
now we sub and find b, the y int
5 = -5(-3) + b
5 = 15 + b
5 - 15 = b
-10 = b
so ur equation is : y = -5x - 10or 5x + y = -10