Stumped on Question!

A Man is on a 24 metre tall Building, and is going to swing from the top of this building to the Bottom of an Identical building on a rope. the Buildings are 24 metres apart, His rope is 24 metres long. He starts from Rest with the rope horizontal, but the rope will break if the tension force in it is twice the weight of the teacher. How high is the swinging man above ground level when the rope breaks?


_________---24 metres---
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|
|XXXXXXX|

Hint, Aparently you use

½mv² = mgh
where h = r-rcosθ

m = mass
g = 9.81 m/s²
v = velocity
h = height
r = radius (24 metres)

 

I dont know where to begin. I've never done this type of question before and sure never learned how to do it. I know bottom is Fc=T-Fg I dont know what to do when its at an angle. I came to a couple of answers where my angle where the rope breaks was 60 but It doesnt get me to the right answer.