Problem 85
Solve the linear system. $$\begin{array}{l}y=4 x \\\x+y=10\end{array}$$
Problem 85
Simplify the expression. $$\frac{8 x}{3} \cdot \frac{1}{x}$$
Problem 85
Solve the equation. $$25 x^{2}-9=-5$$
Problem 86
Solve the linear system. $$\begin{aligned}&3 x+y=12\\\&9 x-y=36\end{aligned}$$
Problem 86
Simplify the expression. $$\frac{8 x^{2}}{3} \cdot \frac{9}{16 x}$$
Problem 86
Solve the equation. $$\frac{1}{7} x^{2}-7=-7$$
Problem 87
Solve the equation. $$-16 t^{2}+48=0$$
Problem 87
Simplify the expression. $$\frac{x}{x+6} \div \frac{x+1}{x+6}$$
Problem 87
Solve the linear system. $$\begin{aligned}&2 x-y=8\\\&2 x+2 y=2\end{aligned}$$
Problem 88
Four American Presidents' faces are carved on Mount Rushmore: Washington, Jefferson, Roosevelt, and Lincoln. Before the faces were carved on the cliff, scale models were made. The ratio of the faces on the cliff to the models was 12 to \(1 .\) If the scale model of President Washington's face was 5 feet tall, how tall is his face on Mount Rushmore?
