Answer:
Explanation:
In order to combine like terms, you have to isolate x and y from one side of the equation.

First, thing you do is remove parentheses.

Solve.
Then, you combine like terms.

Add/subtract the numbers from left to right.
-8z+3.5z=-4.5z
Rewrite the problem down.

Solve.
4.5-1.5=3

- Therefore, the correct answer is 7y+3-4.5z.
I hope this helps, let me know if you have any questions.