Download presentation

Presentation is loading. Please wait.

1
The Sine Rule. A B C ao bo co

2
**Finding The Sine Rule. Consider the triangle below: C A B ao bo co H**

Add the altitude line as shown. H is the height of the triangle. Now write the sine ratio for each right angled triangle: H = A sin bo H = B sin ao Look at these two results and try to work out the next line:

3
C A B ao bo co H = A sin bo B sin ao A sin bo = B sin ao Now divide both sides by sin bo and sin ao . By changing the letters around we can prove that: The Sine Rule.

4
**Calculating Sides Using The Sine Rule.**

Example 1 Find the length of L in this triangle. 10m 34o 41o L Match up corresponding sides and angles: Now cross multiply. Solve for L.

5
Example 2 Find the length of L in this triangle. 10m 133o 37o L Match up corresponding sides and angles: Now cross multiply. Solve for L. = 12.14m

6
What Goes in the Box ? 1 Find the unknown side in each of the triangles below: (1) 12cm 72o 32o A B = 21.8mm (2) 93o B 47o 16mm A = 6.7cm (4) 143o D 12o 17m (3) 87o 89m 35o C C = 51.12m D = 49.21m

7
**Calculating Angles Using The Sine Rule.**

Example 1. ao 45m 23o 38m Find the angle ao Match up corresponding sides and angles: Now cross multiply: Solve for sin ao = 0.463 Use sin to find ao

8
Example 2. 143o 75m 38m bo Find the size of the angle bo Match up corresponding sides and angles: Cross multiply. Solve for sinbo = 0.305 Use sin to find bo

9
**What Goes In The Box ? 2 Calculate the unknown angle in the following:**

(2) 14.7cm bo 14o 12.9cm (1) 14.5m 8.9m ao 100o ao = 37.2o (3) 93o 64mm co 49mm bo = 16o c =49.9o

Similar presentations

Presentation is loading. Please wait....

OK

Areas of Parallelograms & Triangles

Areas of Parallelograms & Triangles

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on textile industry in india Ppt on different occupations for teachers Ppt on new technology in automobile Ppt on google cloud storage Ppt on different occupations in art Esi tof ms ppt online Ppt on natural vegetation and wildlife of the world Ppt on federalism in india Ppt on story of human evolution Ppt on social networking and youth