Question

Alguém me ajuda por favor a resolver essa conta...
(3x+2)(x-1)=x(x+2)
agradeço já pela ajuda

Answer 1

Caso esteja pelo app, e tenha problemas para visualizar esta resposta, experimente abrir pelo navegador https://brainly.com.br/tarefa/38011630

                                           

$\sf(3x+2)\cdot(x-1)=x\cdot(x+2)\\\sf 3x^2-3x+\diagup\!\!\!\!\!\!2x-2=x^2+\diagup\!\!\!\!\!\!2x\\\sf 3x^2-x^2-3x-2=0\\\sf\underbrace{2}_{\sf a}x^2-\underbrace{3}_{b}x-\underbrace{2}_{c}=0\\\sf\Delta=b^2-4ac\\\sf\Delta=(-3)^2-4\cdot2\cdot(-2)\\\sf\Delta=9+16\\\sf\Delta=25\\\sf x=\dfrac{-b\pm\sqrt{\Delta}}{2a}\\\sf x=\dfrac{-(-3)\pm\sqrt{25}}{2\cdot2}\\\sf x=\dfrac{3\pm5}{4}\begin{cases}\sf x_1=\dfrac{3+5}{4}=\dfrac{8}{4}=2\\\sf x=\dfrac{3-5}{2}=-\dfrac{2\div2}{4\div2}=-\dfrac{1}{2}\end{cases}$

$\huge\boxed{\boxed{\boxed{\boxed{\sf S=\left\{-\dfrac{1}{2},2\right\}}}}}$