EXAMPLE 2
Solve
a trigonometric equation
STEP 2
Find the
angle in Quadrant III (where
180° < θ <
270°) that has the same sine
value as the
angle in Step 1. The angle is:
θ
180° + 38.7° = 218.7°
CHECK :
Use a calculator
to check the answer.
5
8
sin 218.7°
– 0.625
=
–
P