Question

-x2+7x-12 (Conta Da fórmula de Bhaskara)

Answer 1

DELTA = $b^2 -4ac$ => DELTA = $7^2 -4.(-1).(-12)$ => DELTA = $49-48$ => DELTA = 1
$x = \frac{-b\frac{+}{-}\sqrt{DELTA}}{2a}$ => $x = \frac{-7\frac{+}{-}\sqrt{1}}{2.(-1)}$ => $x1 = \frac{-6}{-2}$ => $x1 = 3$ / 
$x2 = \frac{-8}{-2}$ => $x2 = 4$
S={ 3, 4}