The slope is (5 - 1) / (-2 - 3) = 4 / -5 = -4/5
Using the slope formula, we have:
(y - 1) / (x - 3) = -4/5
y - 1 = (-4/5)(x - 3)
y - 1 = (-4/5)x + (12/5)
y = (-4/5)x + (17/5)
Note that by the slope formula, if we have a line with slope m and passes through the point (a,b), its equation will be (y - b) / (x - a) = m