Verified answer

You want proof?

God is the answer. The little known Zuwambi sky god to be precise.

There is nothing to connect the unknowns so Quod Erat Demonstrandum [QED], is not applicable.

However, squaring both sides:

D^2 = h^2 + K^2 + L^2

L^2 = D^2 - h^2 -K^2

subsituting for L^2, gives

D^2 = h^2 + K^2 + (D^2 - h^2 - K^2) = D^2 Q.E.D.

Still does not spell sense.

Linked below is the proof to the general form of the Pythagorean Theorem. Enjoy!

P.S. It might be faster for you to get a response if you put this question in the math section.