Question

Responder às funções abaixo : a) 2x(5-x)=x2+3

Answer 1

Olá!

$2x\left(5-x\right)=x^2+3\\\\10x-2x^2=x^2+3\\\\10x-2x^2-3=x^2+3-3\\\\10x-2x^2-3=x^2\\\\10x-2x^2-3-x^2=x^2-x^2\\\\-3x^2+10x-3=0\\\\x_{1,\:2}=\frac{-10\pm \sqrt{10^2-4\left(-3\right)\left(-3\right)}}{2\left(-3\right)}\\\\x_{1,\:2}=\frac{-10\pm \:8}{2\left(-3\right)}\\\\x_1=\frac{-10+8}{2\left(-3\right)},\:x_2=\frac{-10-8}{2\left(-3\right)}\\\\x=\frac{1}{3},\:x=3$

Espero ter ajudado, tenha   boas aulas!