Trigonometry Solving a Right Triangle

Solving a Triangle.. …means to determine all the lengths and angles based on a few known values

Recap- Solving a triangle If we know sides In this case, we know Sin C = opp = 8 Ahyp 10 = B6 C If we know angles and sides In this case we know Sin 53° = opp = AB A hyp Sin 53°= AB 10 (0.7986…)= AB 10 8=AB B 53° C

But… In this case, Sin C = opp = 8 Ahyp 10 = But then all we know is that Sin C= 0.8… B6 C That didn’t give us our angle…

So! New calculator trick In this case, Sin C = opp = 8 Ahyp 10 = Sin C= 0.8 (Sin -1 ) Sin C= (Sin -1 ) 0.8 C= (Sin -1 ) 0.8 B6 C C= 53.13°

Try some more! A D G E 5 F B 3.46 C H 3.5 I Sin A= Cos D= Tan G=

Practice time! P.183 #2,3 Homework: Workbook p.226-p.231, #1,2,3,6,8