We need to do something to both equations so we can eliminate one variable
We can multiply the first equation by 3 and the second equation by 4
3( 4x-2y = 7) yields 12x -6y = 21
4( 3x-3y = 15) yields 12x -12y = 60
Now when we subtract
12x -6y = 21
-(12x -12y = 60)
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12x -6y = 21
-12x +12y = -60
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6y = 39
The x terms are eliminated
Choice D multiply the top equation by 3 and the bottom equation by 4
