When solving for a variable, you get the variable you're trying to solve for on one side and everything to the opposite of that variable.
We have the equation 5w + 9z = 2z + 3w.
Usually the variable we're solving for we want on the left. But it's fine to have it on the right side, too.
Let's subtract 9z from the left-hand side. That way, the 5w will be alone on the left-hand side.
And remember, anything we do on one side we do to the other side.
5w + 9z - 9z = 2z + 3w - 9z
5w = -7z + 3w
The 3w term on the right-hand side needs to be removed. So, subtract each side by 3w.
5w - 3w = -7z + 3w - 3w
2w = -7z
Now, we need to divide each side by 2 to see what the w variable is equal to.
2w / 2 = -7z / 2
w = -7z / 2 or w = -3.5z
So, w is equal to -3.5z.