For the following exercises, use a system of linear equations with two variables and two equations to solve.

A jeep and BMW enter a highway running eastwest at the same exit heading in opposite directions. The jeep entered the highway 30 minutes before the BMW did, and traveled 7 mph slower than the BMW. After 2 hours from the time the BMW entered the highway, the cars were 306.5 miles apart. Find the speed of each car, assuming they were driven on cruise control.