URGENT!

(m + n)  ( m + n)

Multiply  the first term in the first set of parentheses over the two terms in the second set

m * m  + m * n

Multiply the second term in the first set of parentheses over the two terms in the second set

n * m  + n * n

Combine the results

m*m + m*n  + n*m + n*n  =

m^2  + 2mn + n^2