Question 776933
#2 is more fun.


Draw a segment and label length a.  EXTEND the segment and label the extended part length b.  Draw a square using this combined segment of a+b.  LABEL the lengths a and b on each side of the square.  The lengths a and b at right angles to the lengths from these two neighboring sides of this square form FOUR regions.  You can represent the expressions for the areas of each of these four regions.  You find there is a region of area ab and it occurs in this figure TWO times.