\[\boxed{\text{60}\text{\ (60)}\text{.\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ ax = 1\]
\[если\ a = 0 \Longrightarrow 0 \cdot x =\]
\[= 1 - корней\ нет.\]
\[если\ a \neq 0 \Longrightarrow \ x = \frac{1}{a}.\]
\[2)\ ax = a\]
\[если\ a = 0 \Longrightarrow \ \]
\[\Longrightarrow x - любое\ число;.\]
\[если\ \ a \neq 0 \Longrightarrow \ x = \frac{a}{a} = 1.\]
\[3)\ (a - 6)x = a^{2} - 12a + 36\]
\[(a - 6)x = (a - 6)^{2}\]
\[если\ a = 6 \Longrightarrow 0 \cdot x = 0;\ \ \]
\[x - любое\ число.\]
\[если\ a \neq 6 \Longrightarrow x = \frac{(a - 6)^{2}}{(a - 6)};\ \ \]
\[x = a - 6.\]
\[4)\ \left( a^{2} - 4 \right) \cdot x = a - 2\]
\[(a - 2)(a + 2)x = a - 2\]
\[если\ a = - 2:\]
\[- 4 \cdot 0 \cdot x = - 4\]
\[0 \cdot x = 1 \Longrightarrow корней\ нет.\]
\[если\ a = 2:\]
\[0 \cdot 4 \cdot x = 0\]
\[0 \cdot x = 0 \Longrightarrow \ \ x - любое\ число.\]
\[если\ a \neq 2\ \ и\ a \neq - 2:\ \]
\[x = \frac{(a - 2)}{(a - 2)(a + 2)} \Longrightarrow \ \ x =\]
\[= \frac{1}{a + 2}.\]