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Warm-up #3. 1. Sin 23 o = 2. Cos 78 o = 3. Tan 42 o = 4. Sin A = 5. Sin B = 6. Cos A = 7. Cos B = 8. Tan A = 9. Tan B =. A. 13. 12. B. 5. Solving Right Triangles. 9.6 Solving Rt Δ s. Essential Question – How do we solve right triangles and their applications?.
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Warm-up #3 1. Sin 23o = 2. Cos 78o = 3. Tan 42o = 4. Sin A = 5. Sin B = 6. Cos A = 7. Cos B = 8. Tan A = 9. Tan B = A 13 12 B 5
9.6 Solving Rt Δs Essential Question – How do we solve right triangles and their applications?
Solving a right Δ • To solve a rt Δ: find the measure of all its missing parts (should be 3 sides and 3 s). • To find an measure: If sin A=x, then mA= sin-1x If cos A=x, then mA=cos-1x If tan A=x, then mA=tan-1x
Pull out your calculators For inverse sine (sin-1) press 2nd sin For inverse cosine (cos-1) press 2nd cos For inverse tangent (tan-1) press 2nd tan These are also known as arc sin, arc cos, & arc tan.
Ex: Find the measure of the . sin A=.5 tan B=.1051 mA=sin-1.5 mA=30o mB=tan-1.1051 cos A=.7071 mB=6o mA=cos-1.7071 mA=45o
ExampleSolve the Δ mA=sin-1.96 mA=74o A mB=sin-1.28 25 7 mB=16o __ __ B C 24
Ex:solve the Δ (round to the nearest tenth) C 82+102=b2 __ __ 10 64+100=b2 8 164=b2 B A 12.8=b b mA=51.3o mA= tan-11.25 mB=180-90-51.3=38.7o
Example S 15 r=5.1 r __ 20o __ T R s mS=180-90-20 mS=70o
Examplesolve for x 15.7mi __ x __ 59mi tan x=.2661 x= tan-1.2661 x=14.9o