x=17 and y= 10
1) For that linear system, let's multiply the first equation by -2, and then adding:
-2x +2y = -14
2x -3y =4
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-y=-10
y=10
2) Let's plug in the 2nd equation the y-value just found:
2x -3(10)=4
2x -30=4
2x-30+30=4+30
2x=34
x= 17
3) Now we can test, the values by plugging into the equations
x -y = 7 17 -10 = 7 True
2x -3y=4 2(17) -3(10) = 4 True