5х-2(х-3)=6х
6х-(2х+5)=2(3х-6)
х*(х+5)=(х+3)^2
х*(х*(х-1))+6=х*(х+3)*(х-4)
5х-2х+6=6х
5х-2х-6х=-6
-3х=-6
х=2
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6х-(2х-5)=2(3х-6)
6х-2х+5х=6х-12
6х-2х+5х-6х=-12
3х=-12
х=-4
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x^2+5x=x^2+6x+9
x^2+5x-x^2-6x=9
-x=9
x=-9