4. (a) shall have equal roots.

4. (b) Solve the equations

4. (c) Plot the following two equations, and find from the graphs the approximate values of their common solutions:

5. Two integers are in the ratio

Increase each by 15, and the difference of their squares is 999. What are the integers?

6. A man has $539 to spend for sheep. He wishes to keep 14 of the flock that he buys, but to sell the remainder at a gain of $2 per head. This he does and gains $28. How many sheep did he buy, and at what price each?