The solution set sqrt3x+16=x+2 is (only 3x+16 is squared)

Sqrt(3x + 16) = x + 2
3x + 16 = (x + 2)^2 = x^2 + 4x + 4
x^2 + 4x - 3x + 4 - 16 = 0
x^2 + x - 12 = 0
(x - 3)(x + 4) = 0
x - 3 = 0 or x + 4 = 0
x = 3 or x = -4.

Solution set = {-4, 3}