The side of the larger square is x+y
Hence area of the large square=
Show that the area of the large square in the diagram can be written as (x+y)², and also as z²+2xy?
HERE IS THE DIAGRAM http://img43.imageshack.us/img43/9428/trig.png
Do not use pythagoras theorem.
b) Show how these results can be used to prove pythagoras theorem