X^2-y=8
y+x=-2
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x^2-y=8
x=-2-y
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(-2-y)^2-y=8
x=-2-y
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4+4y+y^2-y=8
x=-2-y
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y^2+3y-4=0
x=-2-y
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y1=-4; y2=1
x=-2-y
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y1=-4; y2=1
x1=2; x2=-3
ответ: (2; -4) (-3; 1)
![\dispaystyle log_{11}(x+4)+log_{11}(x-7)=log_{11}(7-x)](https://tex.z-dn.net/?f=%5Cdispaystyle+log_%7B11%7D%28x%2B4%29%2Blog_%7B11%7D%28x-7%29%3Dlog_%7B11%7D%287-x%29)
найдем ОДЗ
![\dispaystyle \left \{ {{x+4\ \textgreater \ 0} \atop {x-7\ \textgreater \ 0; 7-x\ \textgreater \ 0}} \right.\\ \left \{ {{x\ \textgreater \ -4} \atop {x\ \textgreater \ 7; x\ \textless \ 7}} \right.](https://tex.z-dn.net/?f=%5Cdispaystyle++%5Cleft+%5C%7B+%7B%7Bx%2B4%5C+%5Ctextgreater+%5C+0%7D+%5Catop+%7Bx-7%5C+%5Ctextgreater+%5C+0%3B+7-x%5C+%5Ctextgreater+%5C+0%7D%7D+%5Cright.%5C%5C+%5Cleft+%5C%7B+%7B%7Bx%5C+%5Ctextgreater+%5C+-4%7D+%5Catop+%7Bx%5C+%5Ctextgreater+%5C+7%3B+x%5C+%5Ctextless+%5C+7%7D%7D+%5Cright.++)
Одновременно x>7 и x<7 быть не может. Значит решений нет