The given expression to solve is
[tex] (x+y)^2+(x^2+2xy+y^2) [/tex]
As we know that
[tex] (a^2+2ab+b^2)=(a+b)^2 [/tex]
Using the above formula we can write
[tex] x^2+2xy+y^2=(x+y)^2 [/tex]
Hence we can write
[tex] (x+y)^2+(x^2+2xy+y^2)=(x+y)^2+(x+y)^2\\
\\
(x+y)^2+(x^2+2xy+y^2)=2(x+y)^2\\ [/tex]
