Question

Решите систему уравнений 2х-3у=1 и 3х+у=7

Answer 1

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Answer 2

$left { {{2x-3y=1} atop {3x+y=7}} right. /*3 left { {{2x-3y=1} atop {9x+3y=21}} right. left { {{11x=22} x=2 2*2-3y=1 4-3y=1 -3y=-3 y=1$