[tex]x^2-12x + 36 = 4 \\ \\x^2-12x + 36 - 4 =0\\ \\x^2-12x + 32 =0 \\ \\a=1 , \ b=-12, \ c =32\\ \\ \Delta =b^2-4ac = (-12)^2 -4\cdot1\cdot 32 = 144-128 =16\\ \\x_{1}=\frac{-b-\sqrt{\Delta} }{2a}=\frac{12-\sqrt{16}}{2 }=\frac{ 12-4}{2}=\frac{8}{2}= 4[/tex]
[tex]x_{2}=\frac{-b+\sqrt{\Delta} }{2a}=\frac{12+\sqrt{16}}{2 }=\frac{ 12+4}{2}=\frac{16}{2}= 8[/tex]
