Question

MATEMÁTICA!
5) Determine as raizes da seguinte equação: (x+2) (x+3)=3x+5

a) -1
b) -2
c) O
d) 1​

Answer 1

$\displaystyle (x+2)(x+3)=3x+5\\x^2+3x+2x+6=3x+5\\x^2+3x+2x+6-3x-5=0\\x^2+2x+1=0\\\\x=\frac{-b\pm\sqrt{\Delta}}{2a}\\\\x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x=\frac{-2\pm\sqrt{2^2-4.1.1}}{2.1}\\\\x=\frac{-2\pm\sqrt{0}}{2}\\\\x=\frac{-2\pm 0}{2}\\\\\\x'=x''=\frac{-2}{2}=-1$

Alternativa A.