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The wind has blown a tree so that it is growing at a 108° angle with the ground. The top of the tree is 75 ft. from the ground. How tall is the tree?

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Answer: 78.85 ft

Explanation:

Based on the information provided in the exercise, you can draw the right triangle attached, wheree "x" is the height of the tree.

You need to remember the following identity:


sin\alpha=(opposite)/(hypotenuse)

By definition:


\alpha+108\°=180\°

Then, this is:


\alpha=180\°-108\°\\\alpha =72\°

In the right triangle shown in the figure, you can identify:


opposite=75\\hypotenuse=x

Then, you need to substitute the corresponding values into
sin\alpha=(opposite)/(hypotenuse):


sin(72\°)=(75)/(x)

Now, you can solve for "x":


xsin(72\°)=75\\\\x=(75)/(sin(72\°))\\\\x=78.85\ ft

The wind has blown a tree so that it is growing at a 108° angle with the ground. The-example-1
User Jim Stewart
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