- Two planes leave an airport at the same time, one flying at 300 km/h and the other at 420 km/h. The angle between their flight paths is 75 degrees. After three hours, how far apart are they?
- From the top of a building 10 m tall, the angle of elevation to the top of a flagpole is 11 degrees. At the base of the building, the angle of elevation to the top of the flagpole is 39 degrees. Find the height of the flagpole.
- In quadrilateral ABCD, AB=3, BC=4, CD=5, and DA=6. The length of diagonal BD is 7. Find the length of the other diagonal.