\[y = 5x - 8\]
\[a = 5 \cdot ( - a) - 8\]
\[a = - 5a - 8\]
\[6a = - 8\]
\[a = - \frac{8}{6} = - \frac{4}{3}.\]
\[Ответ:точка\ \left( \frac{4}{3};\ - \frac{4}{3} \right).\]