18. On a road in the city of Madison, the maximum speed is 45 miles per hour and the minimum speed is 35 miles per hour. Let x represents the speed. You can write two inequalities to represent the speed restrictions.

maximum speed is 45 mph (x45) minimum speed is 35 mph (x35)

The inequalities x45 and x35 can be combined and can be written without using and.

35x45

a. Explain how compound inequalities can be use to describe the speed restrictions on roads.

b. Include a compound inequality describing a possible age restriction for driving on roads. Describe what this represents. (Minimum driving age is 16 years, and most drivers stop renewing their licenses by age 100.)