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3 years ago

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What is the best approximation of the length of segment QS? (Note: cos 80° = 0.17)

1 answer:

matrenka [14]3 years ago

6 0

Answer: $QS=11.8cm$

Step-by-step explanation:

1. You have the following information:

- The lenght of $RS$ is 2 centimeters.

- The angle m∠S=80°.

- Cos80°=0.17

2. Therefore, you can calculate the lenght of the segment $QS$ as following:

$cos80=\frac{adjacent}{hypotenuse}$

$adjacent=2cm\\hypotenuse=QS\\cos80=0.17$

3. Substitute values and solve for $QS$ :

$0.17=\frac{2cm}{QS}\\QS=\frac{2cm}{0.17} \\QS=11.76cm$

4. To the nearest tenth:

$QS=11.8cm$

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