Question

Find the reference angle for -690 degrees

Answer 1

-690 + 360 = ??
-690 + 360 + 360 = ??

Are we there yet?

Answer 2

Is it 220?

Answer 3

Or 140 degrees

Answer 4

No. Where did you get that?

Note: It really is not helpful just to drop possible answers. Please show your efforts.

Did you do what I suggested?

Answer 5

It's a Reference Angle. Doesn't it have to be between 0º and 90º (inclusive)?

Answer 6

Yes. So -690 + 360 +360=30 degrees

Answer 7

That's it.

Pop Quiz!!!!

If you keep adding or subtracting 360º and you manage 135º when you decide to quit, what is the Reference Angle then?

Answer 8

Would it be 135-90 degrees?

Answer 9

Yes, but that may be by accident.

How about 175º? This will prove that you have it!