1. Use the Law of Sines to find missing side lengths and/or
angle measures in non-right triangles
SECTION 8-6
Law of Sines
Jim Smith JCHS

2. A Car Runs Into A Telephone Pole And
Knocks It Off Perpendicular To The Ground By 9°. If The Pole’s Shadow
Is 57 Feet Long And The Angle Of
Elevation From The Ground To The Top
Of The Pole Is 48°, How Can We Find
The Height Of The Pole?

3. Let a = 7 cm, ∠B = 45°, and ∠C = 75°.
Is there a unique triangle with the given angle and side measures? Why?
How might you determine the measures of the missing angle and sides?

4. What method did we use to find the height of a tree?
What measures did we need to
find the height of a tree or a pole?
If the pole is leaning at an angle,
why can’t we use sin, cos, or tangent?

5. The Law Of Sines Allows Us To Work With Triangles Other Than Right

6. Proportional In A Triangle, The Ratio Of The Sine Of An Angle And
The Length Of The Side Opposite
That Angle Are The Same For
Each Pair Of Angles And Sides.
They are ___________________
Proportional

7. B
Students will be able to write
the law of Sines formula a c A C b

8. A X C B 15 AAS 85° 70° ACT FORM Students will be able
to find the missing side of
a non-right triangle
AAS
85° X B
70° C 15
ACT FORM

9. “Another way to skin a cat”

10. Back To The Car And Telephone Pole
A Car Runs Into A Telephone Pole And
Knocks It Off Perpendicular To The Ground By 9°. If The Pole’s Shadow
Is 57 Feet Long And The Angle Of
Elevation From The Ground To The Top
Of The Pole Is 48°, How Can We Find
The Height Of The Pole?

11. 9°
48° 57
Do you know how to solve it now?

12. B
51° x 9°
81°
48° C A 57

13. Look at a right triangle from
Let’s find an angle…
Look at a right triangle from
last week first … 22 10 x

14. 3 5 x 50° Add This Students will be able to find the missing angle of
a non-right triangle 3 5 x
50°
Add This

15. 14
92° x 17

16. SSA be careful | | |