0.6x^2-1.2x-5.4=0.6x^2+0.9x-0.6x-0.9
-1.2x-0.3x=-0.9+5.4
-1.5x=4.5
x=-3
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<span>{2(3x + 1) + 3(6y -1) = 7
{(3x + 1) - 3(6y - 1) = 8
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сложим
3(3x+1)=15
3x+1=5
3x=4
x=4/3
</span><span>x=1 1/3
</span><span>(3x + 1) - 3(6y - 1) = 8</span><span>
3* 4/3 +1-18y+3=8
4+4-18y=8
18y=0
y=0
ответ (1 1/3;0)
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