x^{2} -8x+18+ \frac{32}{ x^{2} -8x} =0 \\
t+18+ \frac{32}{t} =0 \\
t^2+18t+32=0 \\
D=324-128=196 \\
t= \frac{-18+14}{2}=-2 \\
t= \frac{-18-14}{2}=-16 \\
\left \{ {{ x^{2} -8x=-2} \atop { x^{2} -8x=-16}} \right.= \left \{ {{ x^{2} -8x+2=0} \atop { x^{2} -8x+16=0}} \right.