1. A NSWERS TO H OMEWORK 1) 14.42) 73.83) 16.74) 26.0 5) 9.96) 7.17) 10.38) 5.6 9) 3710) 3411) 2312) 38 13) 5314) 5115) 4616) 27 17) x = 101.8, y = 63.618) x = 26, y = 64 19) x = 27.4, y = 12.220) x = 11.8, y = 10.7 21) x = 13.7, y = 7822) x = 7.1, y = 44 23) x = 88, y = 4624) x = 18, y = 9.3

2. 8-7 A PPLICATIONS OF R IGHT T RIANGLE T RIGONOMETRY Answers to Warm Up Equal Reciprocal

3. E XAMPLE When the sun’s angle of elevation is 38°, a building casts a shadow of 45m. How tall is the building? 38 45 x

4. E XAMPLE From the top of a lighthouse 20m tall, a sailboat is sighted having an angle of depression of 4°. How far from the lighthouse is the boat? 4 20 x

5. TOO: D RAW A PICTURE AND SOLVE ! 1) Two buildings on opposite sides of the street are 40m apart. From the top of the taller building the angle of depression to the top of the shorter building is 13°. How much shorter is the shorter building than the taller building? 2) A road 1.6km long rises 400m. What is the angle of elevation? (Hint: 1000m = 1km) 9m 14°

6. S ECRET C OMPARTMENTS RIGHT TRIANGLES For x: Fill in the sides 10 20 x x x 45 60 30 Solve

7. S ECRET C OMPARTMENTS 45-45-90 30-60-90 45 60 30 x x 2x x x√2 x√3

8. S ECRET C OMPARTMENTS CHAPTER 8 Your Name and Period Writefour common triples anda multiple (x2) What do you use if it’s not a common triple?

9. S ECRET C OMPARTMENTS 3,4,5 10,24,265,12,13 16,30,34 8,15,17 14,48,507,24,25 c 2 = a 2 + b 2 Pythagorean Theorem 6,8,10

10. H OMEWORK Page 318 #1-6 Page 304 #1-7 (Self Test)