What should be added to x2 + xy + y2 to obtain 2x2 + 3xy?

Dear Student

Let us assume p be the required term
Then,
p + (x^2+ xy + y^2) = 2x^2+ 3xy
p = (2x^2+ 3xy) - (x^2+ xy + y^2)
p = 2x^2+ 3xy–x^2–xy–y^2
p = 2x^2–x^2+ 3xy–xy–y^2
p=x^2-2xy–y^2

​Thanks