How do you multiply (3x-2y)^2?

1 Answer
Mar 24, 2015

The special product (A+B)^2=A^2+2AB+B^2
where (in this case) A=3x and B=-2y

Explanation:

Plug that in:

=(3x)^2+2*(3x)(-2y)+(-2y)^2

=9x^2-12xy+4y^2

Or:
If you forgot the special products, you can expand:

=(3x-2y)*(3x-2y)

And then work using FOIL, which means:
First - Outer - Inner -Last

=3x*3x+3x*(-2y)+(-2y) * 3x+(-2y)*(-2y)

Which (of course) wil give the same result.