(x-7)^2=6x+70 помогите

[latex](x-7)^{2}=6x+70[/latex] ........x^{2}-14x+49-6x-70=0 [ [latex] x^{2} -20x-21=0 [/latex] [latex]D=(-20)^{2}-4(-21)=400+84=484 [/latex] [latex] x_{1}= \frac{20+ \sqrt{484} }{2}= \frac{20+22}{2}= \frac{42}{2}=21 [/latex] [latex] x_{2}= \frac{20- \sqrt{484} }{2}= \frac{20-22}{2}= \frac{-2}{2}=-1 [/latex] Ответ: 21:-1