## Introductory Algebra for College Students (7th Edition)

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