Answer:
y=7, x=7
Step-by-step explanation:
They both equal y, so you can set the right part of the equations equal to each other
4x-21=2x-7
solve for x
2x-21=-7
2x=14
x=7
knowing x, we can now substitute back into one of the original equations to find y
y=4(7)-21=28-21=7
or
y=2(7)-7=14-7=7
