# Square of Sum

## Reference > Algebra: Sums and Differences of Squares and Cubes

 DescriptionThe Square of Sum Rule states that:$${(a+b)}^{2}={a}^{2}+2ab+{b}^{2}$$
 Examples${x}^{2}+2xy+{y}^{2}$1 Use Square of Sum: $${(a+b)}^{2}={a}^{2}+2ab+{b}^{2}$$.${(x+y)}^{2}$Done(x+y)^2