Question

2×(x+3)=x²+3x+70 resolva a equação de segundo grau​

Answer 1

Resposta:

$2\left(x+3\right)=x^2+3x+70\\2x+6=x^2+3x+70$

$x^2+3x+70=2x+6\\x^2+3x+64=2x$

$x^2+x+64=0$

$x_{1,\:2}=\frac{-1\pm \sqrt{1^2-4\cdot \:1\cdot \:64}}{2\cdot \:1}$

$x_1=\frac{-1+\sqrt{255}i}{2\cdot \:1},\:x_2=\frac{-1-\sqrt{255}i}{2\cdot \:1}$

$x=-\frac{1}{2}+i\frac{\sqrt{255}}{2},\:x=-\frac{1}{2}-i\frac{\sqrt{255}}{2}$