91Ó°ÊÓ

Solve each system graphically. Check your solutions. Do not use a calculator. $$\begin{aligned}&x^{2}+y^{2}=4\\\&x+y=2\end{aligned}$$

Use Cramer's rule to solve each system of equations. If \(D=0,\) use another method to complete the solution. $$\begin{array}{l}x+y+z=4 \\\2 x-y+3 z=4 \\\4 x+2 y-z=-15\end{array}$$

Find each matrix product if possible. $$\left[\begin{array}{lll}a & b & c \\ d & e & f \\ g & h & i\end{array}\right]\left[\begin{array}{l}x \\ y \\ z\end{array}\right]$$

Solve each system graphically. Check your solutions. Do not use a calculator. $$\begin{aligned}&x^{2}-y=0\\\&x+y^{2}=0\end{aligned}$$

Solve each system. Write solutions in terms of \(z\) if necessary. $$\begin{aligned} 3 x+5 y-z &=0 \\ 4 x-y+2 z &=1 \\ -6 x-10 y+2 z &=0 \end{aligned}$$

Graph the solution set of each system of inequalities by hand. $$\begin{aligned}2 y+x & \geq-5 \\\y & \leq 3+x \\\x & \leq 0 \\\y & \leq 0\end{aligned}$$

Find the equation of the parabola (with vertical axis that passes through the data points shown or specified. Check your answer. $$(2,14),(0,0),(-1,-1)$$

Find the equation of the parabola (with vertical axis that passes through the data points shown or specified. Check your answer. $$(-1,4),(1,2),(3,8)$$

Solve each system. Write solutions in terms of \(z\) if necessary. $$\begin{aligned} x-2 y+z &=5 \\ -2 x+4 y-2 z &=2 \\ 2 x+y-z &=2 \end{aligned}$$

Use Cramer's rule to solve each system of equations. If \(D=0,\) use another method to complete the solution. $$\begin{array}{l}5 x-y=-4 \\\3 x+2 z=4 \\\4 y+3 z=22\end{array}$$