3.6x - 2y = 6
-2.7x + y = 3.....multiply by 2
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3.6x - 2y = 6
-5.4x + 2y = 6 (result of multiplying by 2)
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-1.8x = 12
x = 12/-1.8
x = - 6.67 (or -20/3)
3.6x - 2y = 6
3.6(-6.67) - 2y = 6
-24.01 - 2y = 6
-24.01 - 6 = 2y
-30.01 = 2y
-30.01 / 2 = y
-15 = y
solution : (-6.67, -15)