Graph the system of inequalities and find each corner point. $$\left\{ \begin{array}{r@{}r@{}r} x - 8 y & \ge & -148 \cr -7 x - 5 y & \ge & -184 \cr -9 x+ 9 y & \ge & -36 \cr 15 x+ 4 y & \ge & 136 \cr y & \ge & 0 \cr x & \ge & 0 \end{array} \right.$$
Determine the maximum value of $z=- x+ 8 y$ subject to the given system of linear inequality constraints.

The maximum value of $z$ is at the corner point(s) . If there is more than one corner point, type the points separated by a comma i.e.: (1,2),(3,4).