SOLUTION: The line of sight from a small boat to the light at the top of a 45-foot lighthouse built on a cliff 25 feet above the water makes a 39 degree angle with the water. To the nearest

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Question 452573: The line of sight from a small boat to the light at the top of a 45-foot lighthouse built on a cliff 25 feet above the water makes a 39 degree angle with the water. To the nearest foot, how far is the boat from the cliff?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The line of sight from a small boat to the light at the top of a 45-foot
lighthouse built on a cliff 25 feet above the water makes a 39 degree angle with the water.
To the nearest foot, how far is the boat from the cliff?
:
Let d = distance to the base of the cliff (side adjacent to 39 degree angle)
25 + 45 = 70'; height of lighthouse, side opposite 39 degree angle
:
Tan(39) = 70%2Fd
d = 70%2Ftan%2839%29
d = 86 ft from the base of the cliff
:
Distance from the boat to the cliff (c) itself which is 25' ft above the base, use pythag
c^2 = 25^2 + 86^2
c^2 = sqrt%28625+%2B+7396%29
c = 89.6 ft