Hi, I need some help with this problem:

"A tracking telescope, located 1.25 km from the point of a rocket launch, follows a vertically ascending rocket. Express the height h of the rocket as a function of the angle of elevation θ. Draw a diagram."

I think I have the diagram portion of the problem, but I dont know what do to to solve the problem. I someone could help, can you please include the work, thanks. I have included a picture of MY diagram which I think might be correct.