What is the rate of change of this function

The sum of two numbers is 12 and their difference is 18 what are the two numbers

How is the number of vertices for a prism related to the name of the prism

Abird on top of a 200 ft bridge tower sees a man standing on the lower part of the bridge (which is 50 ft above the ground). the angle of depression from the bird is 26 ̊. how far is the man from the base of the bridge tower? with explanation and pictures .