# How do you multiply (ab + bc)(ab + bc)?

Mar 23, 2017

This can be done using the perfect square formula"

#### Explanation:

$\left(a + b\right) \left(a + b\right) = {a}^{2} + 2 a b + {b}^{2}$

Substituting $a b$ for $a$ and $b c$ for $b$ gives:

$\left(a b + b c\right) \left(a b + b c\right) = {\left(a b\right)}^{2} + 2 a \boldsymbol{c} + {\left(b c\right)}^{2} =$

${a}^{2} {b}^{2} + 2 a {b}^{2} c + {b}^{2} {c}^{2}$