Question

como faço essa conta (x-3)(x+4)+8=x ?

Answer 1

$\\ ( X - 3 ) . ( X + 4 ) +8 = X \\ \\ x^{2} + 4X - 3X - 12 + 8 - X = 0 \\ \\ x^{2} - 4 = 0 \\ \\ x^{2} = 4 \\ \\ X = +- \sqrt{4} \\ \\ X = +- 2 \\ \\ <u>V = { -2, +2}</u>$

Answer 2

$(x - 3) (x + 4) + 8 = x \\ \\ (x - 3) (x + 4) + 8 - x =0 \\ \\ x^{2} + 4x -3x - 12 + 8 - x = 0 \\ \\ x^{2} -4 =0 \\ \\ x= \pm \sqrt{4} \\ \\ x' = 2 \\ \\ x'' = -2$

S = {2, -2}