Question

Equaçoes do 2 grau A)(x-3)(x+2)=-4 B)(x+5)(x-3)-x=5 C)(x+3)(x-4)-52=-x

Answer 1

A)
Aplicando a distributiva:
(x-3)(x+2)=-4
$x^{2} +2x -3x -6=-4$

$x^{2} -x -2=0$

Δ=$b^{2}-4.a.c$

Δ=$(-1)^{2} -4.1.(-2)$

Δ=1+8 = 9

$x_{1} = \frac{-b+ \sqrt{Delta} }{2a} \\ \\ x_{2} = \frac{- b_- \sqrt{Delta} }{2a}$

$x_{1}= \frac{-(-1) + 3 }{2} = \frac{4}{2} = 2 \\ \\ x_{2} = \frac{ -(-1)-3}{2} = \frac{2}{2} =1$