Answer:

Step-by-step explanation:
we know that
step 1
Find 
we know that

we have

substitute



Remember that
Angle theta lie in Quadrant I
so
is positive

Remember that

therefore

step 2
Find 
we know that


we have


substitute


step 3
Find 
we know that

we have

substitute



Remember that

therefore

Answer:
60 degrees
Step-by-step explanation: