Since Ryan is 5 feet tall, we will assume that the height of the cell-phone tower is x + 5. Since the given is 54 degrees. Tan 54degrees = x/80(feet) x=80(tan54) x=110 To finalize the answer, we will add up the height of the cell-phone tower to the answer. 110 + 5 = 115 feet So the answer to the question is that the height of the cell-phone tower is 115 ft.