Answer:
Step-by-step explanation:
Alright, lets get started.
Please refer the diagram I have attached.
If we draw the given angle
, the terminal side will be in second quadrant.
So the reference angle will be the angle between x axis and the terminal side of given angle.
For this, we have to subtract it from 
So the reference angle will be : 
making common denominator
reference angle = 
reference angle =
: Answer
Hope it will help :)