Reference Angle?

Homework question...





Find the reference angle fore each angle with the given measure.





a. -20degrees b. 160degrees c. -545degrees





i'm not sure how to find the answer? can anyone explain? thanks!!

Reference Angle?
If the angle is between 0 and -90, then you can just make it positive.


a) 20 degrees





If the angle is between 90 and 180, then you subtract from 180.


b) 180-60 = 20 degrees





c) If the number is less than -360, then you need to add 360 until you get it above 0.


-545 + 360 = -185.


-185 + 360 = 175.


Since 175 is between 90 and 180, we subtract it from 180.


180-175 = 5