#### Answer

Yes, $-9$ is a solution for this equation.

#### Work Step by Step

To determine whether or not $-9$ is a solution to this equation, we can use $-9$ to substitute for $x$ wherever we see $x$ in the equation. We can then see whether both sides are equal to one another; if they are, then $-9$ would be a solution of the equation:
We now plug $-9$ into the equation:
$3(-9+2) - 15 = 4(-9)$
We follow the order of operations and perform functions in parentheses first:
$3(-7) - 15 = 4(-9)$
We then multiply first before adding or subtracting:
$-21 - 15 = -36$
We now add/subtract:
$-36 = -36$
We see that both sides are equal to one another, so we can conclude that $-9$ is a solution to this equation.