Question

Resolva a equação: x(x – 2) = 2(x + 6)

Answer 1

Olá, tudo bem?

$x(x-2)=2(x+6)\to\\\\x^2-2x=2x+12\to\\\\x^2-4x-12=0\to\\\\\text{Bhaskara}\to\\\\x=\dfrac{-b\pm\sqrt{b^2-4\times a\times c}}{2\times a}\to\\\\\\x=\dfrac{-(-4)\pm\sqrt{(-4)^2-4\times 1\times (-12)}}{2\times 1}\to\\\\\\x=\dfrac{4\pm\sqrt{64}}{2}\tox=\dfrac{4\pm 8}{2}\to\\\\\\x_{1}=\dfrac{4-8}{2}\to\boxed{x_{1}=-2}\\\\\\x_{2}=\dfrac{4+8}{2}\to\boxed{x_{2}=6}$

É isso!! :)