# How do you find the product (4-x)(4+x)?

May 8, 2018

$16 - {x}^{2}$

#### Explanation:

$\text{these are the factors of a "color(blue)"difference of squares}$

•color(white)(x)a^2-b^2=(a-b)(a+b)

$\text{here "a=4" and } b = x$

$\Rightarrow \left(4 - x\right) \left(4 + x\right) = {4}^{2} - {x}^{2} = 16 - {x}^{2}$