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Pls help :Find the missing side or angle.
Round to the nearest tenth.

Pls help :Find the missing side or angle. Round to the nearest tenth.-example-1
User Toi
by
4.2k points

2 Answers

4 votes

Answer:

C° = 71.6056

Explanation:

Law of Cosines: c² = a² + b² - 2abcosC°

Step 1: Plug in known variables

29² = 30² + 15² - 2(30)(15)cosC°

Step 2: Evaluate

841 = 900 + 225 - 900cosC°

-59 = 225 - 900cosC°

-284 = -900cosC°

71/225 = cosC°

cos⁻¹(71/225) = C°

C° = 71.6056

And we have our answer!

User Nicholas Rishel
by
5.0k points
2 votes

Answer:

79.0°

Explanation:

The Law of Cosines is used for this purpose. It tells you ...

a² = b² +c² -2bc·cos(A)

Solving for A gives ...

cos(A) = (b² +c² -a²)/(2bc) = (15² +29²-30²)/(2(15)(29)) = 166/870

Using the inverse cosine function, we find the angle to be ...

A = arccos(166/870) ≈ 79.00026°

A ≈ 79.0°

Pls help :Find the missing side or angle. Round to the nearest tenth.-example-1
User Jayyyyy
by
4.4k points