An observer (O) spots a plane flying at a 35° angle to his horizontal line of sight. If the plane is flying at an altitude of 17,000 ft., what is the distance (x) from the plane (P) to the observer (O)?

Answer Choices-
20,757 feet

24,251 feet

29,639 feet

31,262 feet

I would like an explanation to the question, not just the answer. Will award a medal for the answer to the question.

Question

An observer (O) spots a plane flying at a 35° angle to his horizontal line of sight. If the plane is flying at an altitude of 17,000 ft., what is the distance (x) from the plane (P) to the observer (O)?


Answer Choices- 
20,757 feet

 24,251 feet

 29,639 feet

 31,262 feet


I would like an explanation to the question, not just the answer. Will award a medal for the answer to the question.