KNML is a rectangle. Find the value of x and y

if KNML is indeed a rectangle per se, then if that's true NK = ML, or namely 3y +21 = 5y + 11.

And likewise if it's indeed true, is also true that all interior angles it has are all 90°, or namely 2x - 10 = 90.

c) yes, because of asa or aas