Is it supposed to say 7x rather than Z? If so then
If you make both equations = to 4y you can work out the answer so
4y =7x-4
4y = 36-3x
Then you put them equal to each other so
7x-4 = 36-3x
10x = 40
x = 4
You can then find y by doing
4y = 7x4 - 4
4y = 28-4
4y = 24
y= 6
So the answer is x = 4 and y = 6
