Solve the problem by using an absolute value equation or inequality. See Example 10.Playin...

Solve the problem by using an absolute value equation or inequality. See Example 10.

Playing catch. A circus clown at the top of a 60-foot platform is playing catch with another clown on the ground. The clown on the platform drops a ball at the same time as the one on the ground tosses a ball upward at 80 ft/sec. For what length of time is the distance between the balls less than or equal to 10 feet? (Hint: Use the formula given in Exercise 91. The initial velocity of a ball that is dropped is 0 ft/sec.) See the accompanying figure.

Figure for Exercise 92