Question

решите систему уравнений
5х + 3у =4
2х - у = -5

Answer 1

5x+3y=4
2x-y=-5
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5x+3y=4
y=2x+5
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5x+3(2x+5)=4
y=2x+5
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5x+6x+15=4
y=2x+5
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11x=-11
y=2x+5
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x=-1
y=2(-1)+5=-2+5=3
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/x,y/=/-1,3/
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