\[\boxed{\text{726.}\text{\ }еуроки - ответы\ на\ пятёрку}\]

\[\textbf{а)}\ \text{ab} - 8a - \text{bx} + 8x =\]
\[= \left( \text{ab} - 8a \right) - \left( \text{bx} - 8x \right) =\]
\[= a(b - 8) - x(b - 8) =\]
\[= (b - 8)(a - x)\]
\[\textbf{б)}\ ax - b + bx - a =\]
\[= (ax - a) + (bx - b) =\]
\[= a(x - 1) + b(x - 1) =\]
\[= (x - 1)(a + b)\]
\[\textbf{в)}\ ax - y + x - ay =\]
\[= (ax + x) - (ay + y) =\]
\[= x(a + 1) - y(1 + a) =\]
\[= (x - y)(a + 1)\]
\[\textbf{г)}\ ax - 2bx + ay - 2by =\]
\[= (ax - 2bx) + (ay - 2by) =\]
\[= x(a - 2b) + y(a - 2b) =\]
\[= (a - 2b)(x + y)\ \]


