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

Feb 28, 2016

${x}^{2} - 4 x y + 4 {y}^{2}$

#### Explanation:

${\left(x - 2 y\right)}^{2} = \left(x - 2 y\right) \left(x - 2 y\right)$

To multiply must ensure that each term in the 2nd bracket is multiplied by each term in the 1st bracket

This can be done as follows :

x(x - 2y ) - 2y(x - 2y)

$= {x}^{2} - 2 x y - 2 x y + 4 {y}^{2} = {x}^{2} - 4 x y + 4 {y}^{2}$