ОДЗ x-4>0 и x+7>0
x>4 x>-7
ОДЗ x>4
![\frac{12}{x-4}=x+7 \frac{12}{x-4}=x+7](https://tex.z-dn.net/?f=%5Cfrac%7B12%7D%7Bx-4%7D%3Dx%2B7)
(x-4)(x+7)=12
x²+3x-28-12=0
x²+3x-40=0
D=9+160=169
![x_1=\frac{-3+13}{2}=5 x_1=\frac{-3+13}{2}=5](https://tex.z-dn.net/?f=x_1%3D%5Cfrac%7B-3%2B13%7D%7B2%7D%3D5)
не удовлетворяет ОДЗ
ответ х=5
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