5x-y=7
3x+2y=-1
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y=5x-7
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3x+2(5x-7)=-1
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3x+10x-14=-1
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13x=-1+14
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13x=13
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x=1
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y=5-7, y=-2
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/x,y/=/1,-2/
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3x - y = 6 | * 4
x + 4y = 15;
12x - 4y = 24
13x = 39
x = 3
3 + 4y = 15;
y = 3
Ответ: (3;3)
= 5² + 0.2⁻³ = 5² + (1/3)⁻³ = 5²+5³ = (1+5)*5² = 6*25=150