# How do you solve -6x=x^2+9?

$x = - 3$
${x}^{2} + 6 x + 9 = 0$ set the equation equal to 0
${x}^{2} + 3 x + 3 x + 9 = 0$ find two numbers that MULTIPLY to 9, ADD to 6
$x \left(x + 3\right) + 3 \left(x + 3\right) = 0$ factor out GCF
$\left(x + 3\right) \left(x + 3\right) = 0$
$x = - 3$