What is the sum of all possible values of x such that 2x(x + 10) = -50?
2x(x + 10) = -50 expand to
2x^2 + 20x + 50 = 0 divide by 2 (for simplicity.....you could just use Quadratic Formula here)
x^2 + 10 x + 25 = 0
(x+5)(x+5) = 0 x = -5