21m , 20m , 29m.
(29-21)(29+21) = 20^2
8*50 = 20*20
8*50 = 400 equal!
Yes, it is a right triangle
Use pythagoras's Theorem to check it and if you don't know what that is I suggest you google it.
We need to see if the sum of the squares of the two shorter sides = the square of the longest side
20^2 + 21^2 = 29^2 ???
400 + 441 = 841
And that's true.....so....we have a right triangle....