From a hot air balloon, the angle between a radio antenna straight below and the base of the library downtown is 57°, as shown below. If the distance between the radio antenna and the library is 1.3mls, how many miles high is the balloon?
As you can see in the diagram, the figure formed is a right triangle. Hence, we can use the trigonometric functions. Let's assign x for the altitude of the balloon to be determined.
tan 57 = opposite side/adjacent side tan 57 = 1.3/x x = 1.3/tan57 x = 0.84 miles