\[\frac{x^{2} - 4x + 4}{x^{2} - 6x - 7} \geq 0\]
\[x^{2} - 6x - 7 = x^{2} - 7x + x - 7 =\]
\[= x(x - 7) + (x - 7) =\]
\[= (x - 7)(x + 1)\]
\[\frac{(x - 2)^{2}}{(x - 7)(x + 1)} \geq 0\]