Explanation:
First , put the equation ( by expanding the L side) into ' ax^2 + bx + c' form to use the Quadratic Formula:
3 ( x+4)^2 - 81 =
3 ( x^2 + 8x + 16) - 81 =
3 x^2 + 24 x -33 = 0 now a = 3 b = 24 c = -33
The Quadratic Formula ( see below) then shows
x = - 4 ± 3
