2(n + 5) = -2
First, our goal to this problem is to get the variable (n) and an unknown number on each side. To start off, we can divide both sides by 2.

Second, we can go ahead and cancel 2 out, which will replace it with a -1.

Third, our next step will to be to subtract 5 from each side.

Fourth, our last step is to simplify -1 - 5. This is quite simple. -1 - 5 = -6, so -6 is what the variable (n) equals.

Answer:
Work done on trunk = force * distance = 2 * 3 = 6 joules
Gain in potential energy = 0 joules
My answer is A. Hands down A.
The difference is the subtraction between the numbers;
15-5y
Factor out 5 because it's a common factor;
5(3-y)