91Ó°ÊÓ

Use row operations on an augmented matrix to solve each system of equations. Round to nearest thousandth when appropriate. $$\begin{aligned} &2 x-3 y=10\\\ &2 x+2 y=5 \end{aligned}$$

Checking Analytic Skills Graph the solution set of each system of inequalities by hand. Do not use a calculator. $$\begin{array}{r}x+y \geq 0 \\\2 x-y \geq 3\end{array}$$

\(\begin{aligned} &\frac{2}{x}-\frac{2}{y}+\frac{1}{z}=-1\\\ &\frac{4}{x}+\frac{1}{y}-\frac{2}{z}=-9\\\ &\frac{1}{x}+\frac{1}{y}-\frac{3}{z}=-9 \end{aligned}\)

Solve each system by elimination. $$\begin{array}{c}4 x-y=9 \\\\-8 x+2 y=-18\end{array}$$

Solve each system by using the matrix inverse method. $$\begin{aligned} &2 x-y=-8\\\ &3 x+y=-2 \end{aligned}$$

Evaluate each determinant. $$\operatorname{det}\left[\begin{array}{rrrr}3 & -6 & 5 & -1 \\\0 & 2 & -1 & 3 \\\\-6 & 4 & 2 & 0 \\ -7 & 3 & 1 & 1\end{array}\right]$$

Use row operations on an augmented matrix to solve each system of equations. Round to nearest thousandth when appropriate. $$\begin{aligned} &4 x+y=5\\\ &2 x+y=3 \end{aligned}$$

Solve each system by using the matrix inverse method. $$\begin{array}{c} x+3 y=-12 \\ 2 x-y=11 \end{array}$$

Evaluate each determinant. $$\operatorname{det}\left[\begin{array}{rrrr}4 & 5 & -1 & -1 \\\2 & -3 & 1 & 0 \\\\-5 & 1 & 3 & 9 \\\0 & -2 & 1 & 5\end{array}\right]$$

Checking Analytic Skills Graph the solution set of each system of inequalities by hand. Do not use a calculator. $$\begin{aligned}&x+y \leq 4\\\&x-2 y \geq 6\end{aligned}$$