## Precalculus (6th Edition) Blitzer

The values are, $x=-5,y=6,z=6$.
Consider the given matrices, $\left[ \begin{matrix} 2x & y+7 \\ z & 4 \\ \end{matrix} \right]=\left[ \begin{array}{*{35}{r}} -10 & 13 \\ 6 & 4 \\ \end{array} \right]$ Since the two matrices are equal, the corresponding elements of the two matrices must be the same: \begin{align} & 2x=-10 \\ & y+7=13 \\ & z=6 \end{align} Therefore \begin{align} & x=-5 \\ & y=6 \\ & z=6 \end{align} The required values are $x=-5,y=6,z=6$.