How do you multiply (4m-3n)(4m+3n)?

Jun 23, 2015

$\left(4 m - 3 n\right) \left(4 m + 3 n\right) = 16 {m}^{2} - 9 {n}^{2}$

Explanation:

The general difference of squares can be written as
$\textcolor{w h i t e}{\text{XXXX}}$$\left(a - b\right) \left(a + b\right) = {a}^{2} - {b}^{2}$

Substituting $\left(4 m\right)$ for $\left(a\right)$
and $\left(3 n\right)$ for $\left(b\right)$
in the general form, gives the answer as stated above.