We need to solve the following equation:
[tex]3x+9=-36[/tex]
Solving an equation is the same as finding the value of x.
In order to do so, we need to apply a sequence of the same operations on both sides of the equation, until we isolate the variable x on the left side of the equation, and find its value.
First, let's isolate 3x on the left side. We need to subtract 9 from both sides:
[tex]\begin{gathered} 3x+9-9=-36-9 \\ \\ 3x+0=-45 \\ \\ 3x=-45 \end{gathered}[/tex]
Now, to end with x on the left side, we need to divide both sides by 3:
[tex]\begin{gathered} \frac{3x}{3}=-\frac{45}{3} \\ \\ \frac{3}{3}x=-15 \\ \\ 1x=-15 \\ \\ x=-15 \end{gathered}[/tex]
Answer: B) x = -15
