\[\boxed{\mathbf{857}\mathbf{.}}\]
\[y = kx + b\ \ k = tg\ a\]
\[1)\ a = \frac{\pi}{4},\ \ \ x_{0} = 2,\ \ \ y_{0} = - 3:\]
\[k = tg\ a = tg\frac{\pi}{4} = 1\]
\[- 3 = 2 + b\]
\[b = - 5.\]
\[Ответ:\ \ \ k = 1\ \ b = - 5.\]
\[2)\ a = \frac{\pi}{4},\ \ \ x_{0} = - 3,\ \ \ y_{0} = 2:\]
\[k = tg\ a = tg\frac{\pi}{4} = 1\]
\[2 = - 3 + b\]
\[b = 5.\]
\[Ответ:\ \ k = 1\ \ b = 5\]
\[3)\ a = - \frac{\pi}{3},\ \ \ x_{0} = 1,\ \ \ y_{0} = 1:\]
\[k = tg\ a = - tg\frac{\pi}{3} = - \sqrt{3}\]
\[1 = - \sqrt{3} + b\]
\[b = 1 + \sqrt{3}.\]
\[Ответ:\ \ k = - \sqrt{3}\ \ b = 1 + \sqrt{3}.\]
\[4)\ a = - \frac{\pi}{6},\ \ \ x_{0} = - 1,\ \ \ y_{0} = - 1:\]
\[k = tg\ a = - tg\frac{\pi}{6} = - \frac{\sqrt{3}}{3}\]
\[- 1 = \frac{\sqrt{3}}{3} + b\]
\[b = - 1 - \frac{\sqrt{3}}{3}.\]
\[Ответ:\ \ k = - \frac{\sqrt{3}}{3}\text{\ \ }\]
\[\text{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ }b = - 1 - \frac{\sqrt{3}}{3}.\]