SOLUTION: Having difficulties with this problem: SinA = -5/7 and 180° < A < 270°

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Question 1073694: Having difficulties with this problem:
SinA = -5/7 and 180° < A < 270°
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!

180° < A < 270° is the third quadrant.

We first find the reference angle, which is the angle
whose sine is +5/7.

On your TI-84, press 2ND SIN then press 5/7) ENTER

Read 45.5846914°, which is the reference angle. To
increase it to the desired angle in QIII, we add 180°:

A = 225.5846914°

Edwin