SOLUTION: Find the reference angle for -144 degrees. I'm coming up with 504 degrees, but I think I'm missing a step.

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Question 449192: Find the reference angle for -144 degrees.
I'm coming up with 504 degrees, but I think I'm missing a step.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Find the reference angle for -144 degrees.
I'm coming up with 504 degrees, but I think I'm missing a step.
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The reference angle is ALWAYS an acute angle in the 1st Quadrant.
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504-360 = 144
180-144 = 36
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The reference angle is 36 degrees.
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How to find the reference angle.
Sketch 504 degrees on a unit circle.
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You should find the terminal side
is in the 2nd quadrant at 144 degrees.
---
Draw a vertical line segment from the
point where the terminal side meets
the circle down to the x-axis.
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The acute angle formed by the x-axis
and the terminal side is the reference
angle.
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Note: This procedure will work for finding
any reference angle.
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Example: Find reference for -105 degrees.
1st: Sketch the angle.
It's in the 3rd quadrant.
Draw the vertical line up to the x-axis.
The acute angle formed by the x-axis
and the terminal side is 180-105 = 75 degrees.
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Reference of -144.
-144 is 36 degrees away from the x-axis.
Reference of -144 is 36 degrees.
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Cheers,
Stan H.
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