[tex]4^2(x+6)^2-6^2=4x-6+2x^2\ \ \ |use\ (a+b)^2=a^2+2ab+b^2\\\\16(x^2+12x+36)-36=4x-6+2x^2\\\\16x^2+192x+576-36=4x-6+2x^2\\\\16x^2-2x^2+192x-4x+540+6=0\\\\14x^2+188x+546=0\ \ \ \ |divide\ both\ sides\ by\ 2\\\\7x^2+94x+273=0\\\\a=7;\ b=94;\ c=273\\\Delta=b^2-4ac\to\Delta=94^2-4\cdot7\cdot273=8836-7644=1192 \ \textgreater \ 0\\\\x_1=\dfrac{-b-\sqrt\Delta}{2a};\ x_2=\dfrac{-b+\sqrt\Delta}{2a}\\\\\sqrt\Delta=\sqrt{1192}=\sqrt{4\cdot298}=\sqrt4\cdot\sqrt{298}=2\sqrt{289}[/tex]
[tex]x_1=\dfrac{-94-2\sqrt{298}}{2\cdot7}=\dfrac{-47-\sqrt{298}}{7}\\\\x_2=\dfrac{-94+2\sqrt{298}}{2\cdot7}=\dfrac{-47+\sqrt{298}}{7}[/tex]
