\[\boxed{\text{768\ (768).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ 10\ км;\]
\[2)\ 3\ ч;\]
\[3)\ через\ 2\ часа\ и\ \]
\[через\ 11\ часов;\]
\[4)\ V = \frac{16}{4} = 4\frac{км}{ч};\]
\[5)\ V = \frac{6}{2} = 3\ \frac{км}{ч}\text{.\ }\]
\[\boxed{\text{768.\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ x² + 12x + 36 = 0\]
\[(x + 6)^{2} = 0\]
\[x + 6 = 0\]
\[x = - 6\]
\[Ответ:\ x = - 6.\]
\[2)\ 25x² - 30x + 9 = 0\]
\[(5x - 3)^{2} = 0\]
\[5x - 3 = 0\]
\[x = \frac{3}{5}\]
\[Ответ:x = \frac{3}{5}.\]