From a point 80 feet in front of a library, the angles of elevation to the base of a flagpole, and to the top of the flag are 22° and 43.5°, respectively. find the height of the flagpole to the nearest foot.

In this exercise we have to use the knowledge of trigonometry to calculate the closest point of the library, in this way we find that this value corresponds to:

Thus, we will first use the definition of tangent, which is given by:

So looking at the figure informed, we can see that this formula can be rewritten as:

Now using the new condition and writing in function of the other angle we find that:

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make sure your calculator is in Degree mode.

the answer is y = 11.54

hope this : )