Alright, lets get started.
Please take a look at the diagram attached.
The reference angle of 75 will be 75
As it is mentioned that the angle intersects the unit circle means r = 1
So, finding cos
cos 75 = 
cos 75 = 
cos 75 = 0.259 : Answer
Hope it will help :)
Is this the whole question ?
It's difficult to spot what kind of help is needed.
There's no variable in that equation whose value needs to be found.
It appears to be simply a statement, saying that the tangent of 36 degrees
is (3 and 3/7) .
As such, it's false, since the tangent of 36 degrees is roughly 0.7265 .
What exactly is the question ?
A=pi radius^2
7 is the radius
Pi7^2=153.93
