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A triangular plot of land has angles 46° and 58°........

A triangular plot of land has angles 46° and 58°........-example-1
User Slavo
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1 Answer

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Given the word problem, we can deduce the following information:

1. A triangular plot of land has angles 46° and 58°.

2. The side opposite the 46° is 35 m long.

To determine the length of the fence to enclose the entire plot of land, we make a figure of the triangular plot first:

where:

x= the third angle

a= side opposite of 58°

b= side opposite of x°

Since the sum of the interior angles of a triangle is 180°, we can get the value of x by:

x=180-46-58

x=76°

Next, we use the Law of Sines proportion as shown:


(\sin46)/(35)=(\sin58)/(a)=(\sin x)/(b)

Then, we find the value of a:


\begin{gathered} (\sin46)/(35)=(\sin58)/(a) \\ \text{Simplify and rearrange} \\ a=(\sin58)/((\sin46)/(35)) \\ a=\text{ 41.26 m} \end{gathered}

We also need to find the value of b:


\begin{gathered} (\sin46)/(35)=(\sin x)/(b) \\ \text{Simplify and rearrange} \\ b=(\sin76)/((\sin46)/(35)) \\ b=47.21 \end{gathered}

Hence, we add the sides of which rounded to the nearest meter to get the total length of the fence:

Fence = 35+41+47 =123 meters

Therefore, the length of the fence to enclose the entire plot of land is:

b. 123 meters

A triangular plot of land has angles 46° and 58°........-example-1
User Ashim Dahal
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