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An observer is 175 meters from the base of a building that has a communication tower built on top. The observer measures the angle of elevation to the top of the building and the top of the communication tower to be 55.01° and 57.53° respectively. Calculate the height of the communication tower

User AuRise
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1 Answer

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The height of the communication tower is approximately
\(8.47 \, \text{m}\).

To calculate the height of the communication tower, we can use trigonometry. Let's denote the height of the building as
\(h_{\text{building}}\) and the height of the communication tower as
\(h_{\text{tower}}\).

First, let's consider the angle of elevation to the top of the building. Using the tangent function:


\[ \tan(\text{angle of elevation to building}) = \frac{h_{\text{building}}}{\text{distance to building}} \]


\[ \tan(55.01°) = \frac{h_{\text{building}}}{175 \, \text{m}} \]

Now, solve for
\(h_{\text{building}}\):


\[ h_{\text{building}} = 175 \, \text{m} * \tan(55.01°) \]

Next, consider the angle of elevation to the top of the communication tower:


\[ \tan(\text{angle of elevation to tower}) = \frac{h_{\text{building}} + h_{\text{tower}}}{\text{distance to tower}} \]


\[ \tan(57.53°) = \frac{h_{\text{building}} + h_{\text{tower}}}{175 \, \text{m}} \]

Now, solve for
\(h_{\text{tower}}\):


\[ h_{\text{tower}} = 175 \, \text{m} * \tan(57.53°) - h_{\text{building}} \]

Now, substitute the value of
\(h_{\text{building}}\) into this equation to find
\(h_{\text{tower}}\):


\[ h_{\text{tower}} = 175 \, \text{m} * \tan(57.53°) - (175 \, \text{m} * \tan(55.01°)) \]

Let's calculate the expression to find the height of the communication tower:


\[ h_{\text{tower}} = 175 \, \text{m} * \tan(57.53°) - (175 \, \text{m} * \tan(55.01°)) \]

Using a calculator:


\[ h_{\text{tower}} = 175 \, \text{m} * 1.4724 - (175 \, \text{m} * 1.4284) \]\[ h_{\text{tower}} \approx 257.94 \, \text{m} - 249.47 \, \text{m} \]\[ h_{\text{tower}} \approx 8.47 \, \text{m} \]

Therefore, the height of the communication tower is approximately
\(8.47 \, \text{m}\).

User Oneida
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