x=5 y=15 (5,15).
This is how you do it:
-4(2x+3y=55): -8x-12y=-220
3(9x+4y=105):27x+12y=315
You add the two new equations together, canceling out the y values, and get the x value. Then, you go back and plug in the x value in the original equation to get the y value.
