Chapter 9 Review

Well, this week is the trig test so I thought it would be a good idea to review a trig chapter. This week I am going to review with you all the information that we learned in Chapter 9. Chapter 9 is all about triangles. There are a few formulas that you need to know for this chapter.

Notes:
• SOHCATOA: sin (theta) = opp. / hyp. cos (theta) = adj. / hyp. tan (theta) = opp./adj.
• To find the area of a right triangle, use the formula A=½ bh
• To find the area of a non right triangle, use the formula A= ½ (adj.) (adj.) sin(angle b/w)
• Law of Sines: (sin A / a) = (sin B / b) = (sin C / c)
• Law of Cosines: opp. leg^2 = (adj. leg^2) + (other adj. leg^2) – 2(adj. leg) (other adj. leg) cos (angle b/w)

Example: Find the area of non right triangle ABC when: AB=4, BC=6, and B=60 degrees
• ½ (4) (6) sin (60 degrees)
• 12 sin (60 degrees)
• A=10.392 u^2


-Braxton-