You can put this solution on YOUR website!
Let P=(x+y)
Then: That is a more familiar looking quadratic equation.
(P___)(P____) we need to fill the blanks with two numbers that multiply to give you +2, but add to give you +3.
2*1=2, but 2+1=3
(P+2)(P+1) But P=(x+y), so...
((x+y)+2)((x+y)+1)
(x+y+2)(x+y+1)
Happy Calculating!!!