Warm-up 12.4 Law of Cosines

# Warm-up 12.4 Law of Cosines

## Warm-up 12.4 Law of Cosines

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
##### Presentation Transcript

1. Warm-up12.4 Law of Cosines A new house is 32 feet wide. The rafters will rise at a36° angle and meet above the center line of the house. Each rafter also needs to overhang the side of the house by 2 feet. How long should the carpenter make each rafter? Draw the picture. Solve for ?

2. pg 648 #1-9 and pg 657 and 658 #1-10 12.2 pg 648 #1-9 12.3 pg 657 and 658 #1-10

3. Pythagorean Identity

4. 12.4 Law of Cosines Pg 661 Law of Cosines:

5. More Problems

6. Word Problems 6) During a storm, a tree cracks and bends over touching the ground. The tip of the tree touches the ground 25 feet and 6 inches from the base of the tree forming a 36 degree angle with the ground. What was the tree’s original height? Show your work for credit! Original Tree Height: _______________ 7)Two 12 centimeter radii of a circle form a central angle measuring 120 degrees. What is the length of the chord connecting the two radii? Draw a picture described in 10). Chord length: __________ 8) To the nearest meter, find the length of side DE in DDEF given mÐF = 54°, DF = 80 m, and EF = 50 m. Length of DE = ________________