\[\boxed{\text{410\ (410).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[(x - 3)^{2} + (y - 8)^{2} = r^{2}.\]
\[\textbf{а)}\ точка\ касания\ (3;0):\ \ \ \]
\[(3 - 3)^{2} + (0 - 8)^{2} = 64;\]
\[(x - 3)^{2} + (y - 8)^{2} = 64.\]
\[\textbf{б)}\ точка\ касания\ (0;8):\ \ \]
\[(0 - 3)^{2} + (8 - 8)^{2} = 9;\]
\[(x - 3)^{2} + (y - 8)^{2} = 9.\]
\[\boxed{\text{410.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]
\[\left( \frac{a + 1}{a - 1} - \frac{a - 1}{a + 1} \right)\ :\frac{4a}{5a - 5} =\]
\[= \frac{4a}{(a - 1)(a + 1)} \cdot \frac{5 \cdot (a - 1)}{4a} =\]
\[= \frac{5}{a + 1}\]
\[При\ a > - 1:\ \ \]
\[\frac{5}{a + 1} > 0.\ \]