Question

Simplify (3n - 2m)2 = ?

Answer 1

`(3n-2m)^2\\\\use\ (a-b)^2=a^2-2ab+b^2\\\\(3n-2m)^2=(3n)^2-2\cdot3n\cdot2m+(2m)^2\\\\=\boxed{9n^2-12mn+4m^2}`