Question

2(x+3)^2 - 10x - 7 = 21 -2 (x-1) (x+1)

Answer 1

Solución:

2(x+3)² - 10x - 7 = 21 - 2(x-1)(x+1)
2(x²+6x+9) - 10x - 7 = 21 - 2(x² -1)
2x² + 12x + 18 - 10x - 7 = 21 - 2x² + 2
4x² + 2x - 12 = 0
2x² + x - 6 = 0
(2x-3)(x+2) = 0

x = 3/2 ó x = -2

Saludos!