I have only been able to set up the solution to this problem, but am completely stuck on how to proceed. All help is greatly appreciated.

The problem:*A bicyclist averages one speed uphill, one speed on level ground, and one speed downhill. She estimates the following mileage for her thrwe previous rides:*

*2 miles uphill, 15 miles level, 5 miles downhill - 1.5 hours*

*6 miles uphill, 9 miles level, 1 miles downhill - 1.4 hours*

*8 miles uphill, 3 miles level, 8 miles downhill - 1.6 hours*

*What were her average speeds uphill, on level ground and downhill?*

My partial solution:Using U, L and D for uphill, level and downhill speeds, respectively, here are the set of equations I have set up:

- 2/U + 15/L + 5/D = 1.5
- 6/U + 9/L + 1/D = 1.4
- 8/U + 3/L + 8/D = 1.6

Assuming this is right, now what?