# Question #55edb

##### 1 Answer

The angle should measure

#### Explanation:

I keep the CAST abbreviation rule in mind when doing these types of questions. Starting from quadrant IV and going counter-clockwise, the letters determine which trigonometric function will turn out positive in each quadrant.

**C** osine, **A** ll, **S** ine, **T** angent.

So for background information, it makes sense that sin would be positive in the second quadrant.

If **reference angle** in quadrant I.

Now, here's the rule:

If the angle is in quadrant II;

#"180 degrees - reference angle = answer"#

And as an extra, quadrant III:

#"180 degrees + reference angle = answer"#

Finally, quadrant IV:

#"360 degrees - reference angle = answer"#

So

Hope this helps!

Best wishes,

A fellow highschool student.