PLEASE HELP IM STUCK

Step-by-step explanation:
we have
2y = 4x - 9
and we want it to look like
...x + ...y = -9
simple.
the y term is already on the left side. we need to move the x term to the same side.
what do we do ? we subtract the term we want to get rid of on one side from both sides (we always have to do changes in both sides of the equation, or we change the whole meaning of the equation).
2y = 4x - 9 | -4x on both sides
-4x + 2y = -9
and we are finished. that's it.