10x + 13y = 11....multiply by 3
3x + 14y = -27....multiply by -10
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30x + 39y = 33 (result of multiplying by 3)
-30x - 140y = 270 (result of multiplying by -10)
-------------------add
- 101y = 303
y = 303/-101
y = -3
10x + 13y = 11
10x + 13(-3) = 11
10x - 39 = 11
10x = 11 + 39
10x = 50
x = 50/10
x = 5
solution is : (5,-3)
