Math 45

Sample Second Midterm

Dr. Wilson

1. Suppose you get a job selling T-shirts at a concert. You get $2 for each T-shirt you sell, but it costs you $5 to get into the concert. How many T-shirts will you have to sell in order to come home with $25?

In 2 - 7, solve for x and check.


3. Solve for x and check. 2x2 - x - 10 = 0.

In problem 3, solve by factoring, completing the square, and the quadratic formula.





Solve for   x   and check

8. Linda goes to visit a friend who lives in Lompoc. It is 390 miles from Linda's house to her friend's house. When she came back, it took her a half an hour less time and her average speed was 5 miles per hour faster. How fast was she going when she went down to Lompoc, and how fast was she going when she drove back?

9. Linda drives from Ukiah to the East Bay. She averages 60mi/hr on the freeway, but when she gets to the East Bay, the freeway is clogged with rush hour traffic. Fortunately, she knows the East Bay, and knows how to get to her destination on surface streets. Unfortunately, she can only average 30mi/hr on the surface streets. The trip was 150 miles long and it took her 3 hours. How long was she on the freeway and how long was she on the surface streets. How far did she drive on the freeway and how far did she drive on the surface streets?

10. Derive the quadratic formula by solving the equation

ax2 + bx + c = 0

by completing the square, and check the solution.