1. Sections 10.1-10.2 Law of Cosines and Law of Sines
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2. REVIEW JEOPARDY RULES
ONE PERSON WILL ANSWER THE QUESTION FOR EACH GROUP
ANSWERS SHOULD BE TO THE TENTHS DECIMAL PLACE.
GROUPS CANNOT WHISPER ANSWERS TO THIER PERSON OR HELP THEM IN ANY WAY
EVERYONE MUST TAKE A TURN ANSWERING A QUESTION
ONCE YOU RING IN, YOU HAVE 5 SECONDS TO ANSWER
ANSWERS DO NOT HAVE TO BE IN QUESTION FORM
EVERYONE SHOULD BE DOING EACH PROBLEM. YOUR WORK WILL BE CHECKED AT THE END OF THE PERIOD.

3. Area of an Oblique Triangle
REVIEW JEOPARDY
Law of Cosines
Law of Sines
Ambiguous Cases
Area of an Oblique Triangle
Heron’s Formula 10 10 10 10 10 20 20 20 20 20 30 30 30 30 30 40 40 40 40 40 50 50 50 50 50

4. Find the missing parts of the oblique triangle with
Law of Cosines– 10 Points
Find the missing parts of the oblique triangle with
B = 40º, a = 12, and c = 20.
b ≈ 13.3, A ≈ 35.5º, and C ≈ 104.5º

5. Find the angles of a triangle whose vertices are
Law of Cosines– 20 Points
Find the angles of a triangle whose vertices are
A(0,0), B(5,-2), and C(1,-4).
A ≈ 54.2º, B ≈ 48.4º, and C ≈ 77.4º

6. Law of Cosines– 30 Points
Two trains leave a station on different tracks. The tracks make a 112º angle with the station as a vertex. The first train travels at an average speed of 90 kilometers per hour and the second at an average speed of 55 kilometers per hour. How far apart are they after 2 hours and 45 minutes?
334.9 km

7. Law of Cosines– 40 Points
The pitcher’s mound on a standard baseball diamond (which is actually a square) is 60.5 feet from home plate. How far is the pitcher’s mound from first base?
63.7 feet

8. Law of Cosines– 50 Points
Two ships leave port, one traveling in a straight course at 22 mph and the other traveling in a straight course at 31 mph. The courses diverge at 38º. How far apart are they after 3 hours?
57.7 miles

9. Find the missing parts of the oblique triangle with
Law of Sines– 10 Points
Find the missing parts of the oblique triangle with
B = 33º, C = 46º, and b = 4.
A = 101º, a ≈ 7.2, and c ≈ 5.3

10. Find the missing parts of the oblique triangle with
Law of Sines– 20 Points
Find the missing parts of the oblique triangle with
B = 97.5º, C = 42.5º, and b = 7
a ≈ 4.5, c ≈ 4.8, and A = 40

11. Find the missing parts of the oblique triangle with
Law of Sines– 30 Points
Find the missing parts of the oblique triangle with
a = 9, b = 14, and B = 95º.
A ≈ 39.8º, C ≈ 45.2º, and c ≈ 10.0

12. Law of Sines– 40 Points
A side view of a bus shelter is shown in the following figure. The brace d makes an angle of 37.25º with the back and an angle of 34.85º with the top of the shelter. How long is the brace?
5.0 feet

13. Law of Sines– 50 Points
Two straight roads meet at an angle of 40º in Harville, one leading to Eastview and the other to Wellston (see figure). Eastview is 18 kilometers from Harville and 20 kilometers from Wellston. What is the distance from Harville to Wellston?
30.1 km

14. Ambiguous Cases– 10 Points
Find the missing parts of the oblique triangle with
b = 30, c = 50, and C = 60º.
A ≈ 88.7º, B ≈ 31.3º, and a ≈ 57.7

15. Ambiguous Cases– 20 Points
Find the missing parts of the oblique triangle with
b = 15, c = 25, and B = 47º.
No solution

16. Ambiguous Cases– 30 Points
Find the missing parts of the oblique triangle with
a = 50, c = 80, and C = 45º.
A ≈ 26.2º, B ≈ 108.8º, and b ≈ 107.1

17. Ambiguous Cases– 40 Points
Find the missing parts of the oblique triangle with
b = 24.1, c = 10.5, and C = 26.3º.
No solution

18. Ambiguous Cases– 50 Points
Find the missing parts of the oblique triangle with
a = 30, b = 40, and A = 30º.
1: B ≈ 41.8º, C ≈ 108.2º, and c ≈ 57.0
2: B ≈ 138.2º, C ≈ 11.8º, and c ≈ 12.3

19. Area of an Oblique Triangle– 10 Points
Find the area of a triangle with b = 10, c = 14, and A = 36º
41.1 sq units

20. Area of an Oblique Triangle– 20 Points
Find the area of a triangle with a = 9, b = 13, and C = 75º
56.5 sq units

21. DAILY DOUBLE Area of an Oblique Triangle– 30 Points
Find the area of a triangle with a = 17, b = 27, and c = 40
177.6 sq units

22. Area of an Oblique Triangle– 40 Points
Find the area of a triangle with vertices A(0,0), B(2,-5),
and C(-3,1).
6.5 sq units

23. Area of an Oblique Triangle– 50 Points
Find the area of the triangle ABE. B A C
393.9 sq units E D

24. Heron’s Formula– 10 Points
Find the area of a triangle with a = 4, b = 12, c = 14.
22.2 sq units

25. Heron’s Formula– 20 Points
Find the area of a triangle with a = 7, b = 9, and c = 11.
31.4 sq units

26. Heron’s Formula– 30 Points
Find the area of a triangle with c = 7, a = 10, B = 68º.
32.4 sq units

27. Heron’s Formula– 40 Points
If a gallon of paint covers 400 square feet, how many one gallon buckets are needed to paint a triangular deck with the sides of 65 feet, 72 feet, and 88 feet?
6 buckets

28. Heron’s Formula– 50 Points
What is the area of a triangle whose sides have lengths 12, 20, and 36?
(HINT: Draw a picture of the triangle)
The triangle does not exist.