Question 172264
sqrt(x+7) - 2sqrt(x) = -2
sqrt(x+7) = 2sqrt(x) - 2
Square both sides
(x+7) = 4x -8sqrt(x) + 4
-3x + 3 = -8sqrt(x)
Square again
9x^2 - 18x + 9 = 64x
9x^2 + -82x + 9 = 0
*[invoke solve_quadratic_equation 9,-82,9]
The factors are not correct, but the answers are.
x = 9
x = 1/9