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To determine the distance across a pond, Harrymade the measurements shown in the diagram.ROS20 m80°TWhich is closest to the distance from R to S?3.48 m19.7 m20.3 m113.4 m

To determine the distance across a pond, Harrymade the measurements shown in the diagram-example-1
User Ilya Degtyarenko
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1 Answer

12 votes
12 votes

From the drawing made, we can see that a triangle with a right angle is form, thus, a right triangle.

Since this is a right triangle, the properties of sine, cossine and tangent apply. RS is the leg opposite to the 80° angle, while 20m is the length of the hypotenuse. So we can use sine to find RS.


\begin{gathered} \sin 80\degree=(RS)/(ST)=(RS)/(20) \\ RS=20\sin 80\degree\approx20\cdot0.9848=19.696\approx19.7 \end{gathered}

So, the closest alternative is 19.7 m.

User Zaelin Goodman
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