3x + 4y = 17.....multiply by 4
-4x - 3y = -18 ...multiply by 3
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12x + 16y = 68 (result of multiplying by 4)
-12x - 9y = - 54 (result of multiplying by 3)
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7y = 14
y = 14/7
y = 2
3x + 4y = 17
3x + 4(2) = 17
3x + 8 = 17
3x = 17 - 8
3x = 9
x = 9/3
x = 3
ur solution is (3,2)