If two overlapping waves have the same amplitude then what happens?

I think the answer could be that it could result in resonance.

There is not much to go from in this question. Specify whether the are on the same wave length or on separate.

If the 2 waves are on the same wave length and going towards each other with the same amplitude, that would result in them colliding and forming a larger amplitude, or something called constructive interference.

I hope this helps you!

15.3 cos 65 degrees trig