\[\boxed{\text{262.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]
\[\textbf{а)}\ \frac{2ab + 2by + ay + y^{2}}{2ab - 2by + ay - y^{2}} =\]
\[= \frac{a \cdot (2b + y) + y(2b + y)}{a(2b + y) - y(2b + y)} =\]
\[= \frac{(2b + y)(a + y)}{(2b + y)(a - y)} =\]
\[= \frac{a + y}{a - y}.\]
\[(В\ учебнике\ опечатка).\]
\[\textbf{б)}\ \frac{9x^{2} + 6x + 4}{27x^{3} - 8} =\]
\[= \frac{9x^{2} + 6x + 4}{(3x - 2)\left( 9x^{2} + 6x + 4 \right)} =\]
\[= \frac{1}{3x - 2}.\]