91Ó°ÊÓ

Use two equations in two variables to solve each application. Bill invested some money at \(5 \%\) annual interest, and Janette invested some at \(7 \%\). If their combined interest was $$ 310\( on a total investment of $$ 5,000,\) how much did Bill invest?

Solve each system by graphing. SEE EXAMPLE 3. (OBJECTIVE 3) $$\left\\{\begin{array}{l} x=2 y-8 \\ y=\frac{1}{2} x-5 \end{array}\right.$$

Use substitution to solve each system. $$\left\\{\begin{array}{l}3 a+6 b=-9 \\\a=4-2 b\end{array}\right.$$

Use elimination to solve each system. $$\left\\{\begin{array}{l}3 y=4 x \\\5 x=4 y-2\end{array}\right.$$

Use two equations in two variables to solve each application. Peter invested some money at \(6 \%\) annual interest, and Martha invested some at \(12 \%\). If their combined investment was $$ 6,000\( and their combined interest was $$ 540,\) how much money did Martha invest?

Use two equations in two variables to solve each application. Students can buy tickets to a basketball game for \(\$ 1 .\) The admission for nonstudents is \(\$ 2 .\) If 350 tickets are sold and the total receipts are \(\$ 450,\) how many student tickets are sold?

Use elimination to solve each system. $$\left\\{\begin{array}{l}3 x-2 y=-1 \\\2 x+3 y=-5\end{array}\right.$$

Use substitution to solve each system. $$\left\\{\begin{array}{l}a=\frac{3}{2} b+5 \\\2 a-3 b=8\end{array}\right.$$

Solve each system by graphing. Give each answer as a general ordered pair. SEE EXAMPLE 4. (OBJECTIVE 4) $$\left\\{\begin{array}{l} 4 x-2 y=8 \\ y=2 x-4 \end{array}\right.$$

Graph the solution set of each system of inequalities, when possible. SEE EXAMPLE 6. (OBJECTIVE 4) $$\left\\{\begin{array}{l} x+2 y \leq 3 \\ 2 x-y \geq 1 \end{array}\right.$$