\[\boxed{\text{427\ (427).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[1)\ \overline{1x} + \overline{2x} = \overline{x6}\]
\[10 + x + 20 + x = 10x + 6\]
\[- 8x = - 24\]
\[x = 3.\]
\[Ответ:x = 3.\]
\[2)\ \overline{x4} + \overline{x8} = \overline{1x2}\]
\[10x + 4 + 10x + 8 =\]
\[= 100 + 10x + 2\]
\[10x = 90\]
\[x = 9.\]
\[Ответ:x = 9.\ \]