5x-5(3-x)=x в квадрате + 10

[tex]5x - 15 + 5x = {x}^{2} + 10 \\ {x}^{2} - 10x + 25 = 0 \\ {(x - 5)}^{2} = 0 \\ x - 5 = 0 \\ x = 5[/tex]

10x-15=x2+10
-x2+10x-25=0
x2-10x+25=0
(x-5)2=0
x=5