Let (theta) be the angle of elevation from point on the ground to the top of a tree. If cos (theta)=11/61 and the distance from the point on the ground to the base of the tree is 22ft, then how tall is the tree?
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If you know your SOHCAHTOA then you know that \(\cos\theta = \dfrac{adj}{hyp} =\dfrac{22~ft}{hyp} \) We are told \(\cos \theta = \dfrac{11}{61} \) That means \(\dfrac{22~ft}{hyp} = \dfrac{11}{61 } \) We can solve for the hypotenuse: \(hyp = \dfrac{61 \times 22~ft }{11} = 122 ~ft\)
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Now you can use the sine or the Pythagorean theorem to find the height of the tree.
\[x^{2}+y ^{2}= r ^{2}\] right?
yes
Thank you so much for taking the time. :)
You're welcome.
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