Question

as raizes de x + 2x + - 9 igual 0 sao

Answer 1

x+2x±9=0
3x±9=0
3x=±9
$x = \frac{ + - 9}{3}$
$x1 = \frac{ - 9}{3} = - 3 \\ x2 = \frac{9}{3} = 3$