x + y = 179..........multiply by 3
2/3x + 3/4y = 128...multiply by -4
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3x + 3y = 537 (result of multiplying by 3)
-8/3x - 3y = -512 (result of multiplying by -4)
--------------add
1/3x = 25
x = 25 * 3
x = 75
x + y = 179
75 + y = 179
y = 179 - 75
y = 104
lines that should be checked are : 1,4,7