SOLUTION: Boat is 65.7 M away from the base of the Cliff. Giving that the angle of depression of the boat from the top of the Cliff is 28.9°, find the height of the Cliff.

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Question 1132626: Boat is 65.7 M away from the base of the Cliff. Giving that the angle of depression of the boat from the top of the Cliff is 28.9°, find the height of the Cliff.
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617)   (Show Source):
You can put this solution on YOUR website!

~~119 M high~~

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Height, unknown y

Angle of depression same as angle of elevation from boat to top of cliff, 28.9 degrees.

Answer by ikleyn(52787)   (Show Source):
You can put this solution on YOUR website!
.

            The solution and the answer by @josgarithmetic both are   W R O N G.

            For your safety, simply ignore it.

            Below is my solution, which is correct.

In this problem, tan(28.9°) = , where H is the height of the cliff and L is the distance from the base of the cliff. Hence, H =L*tan(28.9°) = 65.7*0.552 = 36.27 meters. ANSWER

The lesson to learn from my post is   T H I S:

To solve this problem in a right way, you need to know what the angle of depression is. Learn it from this link https://www.varsitytutors.com/hotmath/hotmath_help/topics/angles-of-elevation-and-depression https://www.varsitytutors.com/hotmath/hotmath_help/topics/angles-of-elevation-and-depression

                    H a p p y   l e a r n i n g ! !