Name: _________________
Worksheet on the Law of Sines and the Law of Cosines
1.Warm-up.
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a. Find two different angles that both have a sine of .
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b. Find two different angles that both have a cosine of 
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2. Warm-up: How to…
To do problem 1(a) using your calculator:
Set your calculator to degree mode.
Look for either "asin" or "sin-¹" on your calculator.
Press this key. (You may have to use the "2nd" key to access it.)
Then type “1/2” and press Enter.
The calculator gives you only the angle that is in the first quadrant.
To get the other angle, you will have to figure it out by using the
first angle as a reference.
a. Find two different angles that both have a sine of (1/3).
b. Find two different angles that both have a cosine of 0.7
3. Find the area of each triangle below:
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4. For each triangle below, fill in all of the angles:
5. Use the Law of Sines to find x.
6. Complete each triangle.
7. Complete each triangle.
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8. Use the Law of Cosines to find x.
9. Complete each triangle.
10. Sketch two different triangles such that: a = 19, b = 25, A = 43º.
11. Solve the two triangles you sketched in problem 10.
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