Question

Solve the following quadratic equation by the square root property of equality. 2(x + 7)^2 = 64

Answer 1

$2(x+7)^2=64\ \ \ \ |:2\\\\(x+7)^2=32\to x+7=\pm\sqrt{32}\\\\x+7=-\sqrt{16\cdot2}\ \vee\ x+7=\sqrt{16\cdot2}\\\\x+7=-\sqrt{16}\cdot\sqrt2\ \vee\ x+7=\sqrt{16}\cdot\sqrt2\\\\x+7=-4\sqrt2\ \vee\ x+7=4\sqrt2\ \ \ \ |-7\\\\\boxed{x=-7-4\sqrt2\ \vee\ x=-7+4\sqrt2}$