Question

y elevado a 2 - 11 y +18 = 0

Answer 1

$y ^{2} - 11y + 18 = 0$
$y^{2} + 9y + 2y + 18 = 0 \\ \\ y(y + 9) + 2(y + 9) = 0 \\ \\ (y + 9) \times (y + 2) = 0 \\ \\ y + 9 = 0 \\ y + 2 = 0 \\ \\ y = - 9 \\ y = - 2 \\ \\ y1 = - 9 \\ e \\ y2 = - 2$