using the method of elimination by addition and subtraction. Notice that if we multiply all terms of the first equation by 3 and all terms of the second by 4, y as a variable will temporarily disappear:
9x + 12y = 15
8x - 12y = -32
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17x = - 17, so x = -1.
Replacing x in the second equation by -1, we get:
2(-1) - 3y = -8, or
2 + 3y = 8,
or 3y = 6. Thus, y = 2, and the solution is (-1, 2).
