Calculus Triangle Related Rate
So I have a problem where there is a right triangle with the height (4500ft) and the rate at which the angle is changing (pi/180radians per second) and I need to find the ground speed.
I figured out that the ground speed dx/dt=-4500csc^2(theda) d(theda)/dt
But after this I am stuck. I really need help because I just don't get how I'm supposed to find the speed, please help as soon as possible I am forever thankful.
Also I kind of got an answer of 1272 mph, is there any chance that is even possibly right?