Question

what move can you make to both sides of the equation to get rid of the -3n on the right, so that all the n terms are on the left side of the equation?
options: subtract 3n from both sides, add 3n to each side, divide each side by 3n, multiply each side by 3n

Explanation:

Step1: Identify target term removal

We aim to eliminate $-3n$ on the right side. To cancel a $-3n$, we use its additive inverse.

Step2: Apply inverse operation

The additive inverse of $-3n$ is $3n$. Adding $3n$ to both sides will eliminate $-3n$ on the right, and collect $n$-terms on the left:
Left side: $2n + 3n + 9 = 5n + 9$
Right side: $-3n + 3n + 13 = 13$

Answer:

Add 3n to each side