A pentagon can be divided into five congruent triangles. The function t=5 tan theta models the height of each triangle. what is the area of the pentagon if theta=54 degrees? round to the nearest foot.

Question

e.mccormick · Answer

Did you try finding the angles of the triangles?

e.mccormick · Answer

np.  We all have it happen sometime.  I got 86 doing it sligly differently because I did not notice 5 was the base... and I am looking at my answer and yours scrating my head.  Hehe.  So I did it again.

Yesterday I swapped (3-x) for (x-3) on someone.  Not like I am perfect myself!

e.mccormick · Answer

Then they are doing 10 triangles.  Not 5...  It is a poorly written question.

e.mccormick · Answer

Take the pentagon.
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e.mccormick · Answer

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e.mccormick · Answer

$\tan54^\circ = \dfrac{x}{5}$ Well, that means the adjacent side is 5. But what is the adjacent side?

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This means you are really working with 10 triangles that have a side of 5 or 5 triangles with a side of 10.  

That is why the original version by Euler271 was incorrect on one and only one point and there was so much argument that I have deleted.

Now, finish it on your own.