4x2164{x}^{2}-16

1
Find the Greatest Common Factor (GCF).
GCF = 44

2
Factor out the GCF. (Write the GCF first. Then, in parentheses, divide each term by the GCF.)
4(4x24164)4(\frac{4{x}^{2}}{4}-\frac{16}{4})

3
Simplify each term in parentheses.
4(x24)4({x}^{2}-4)

4
Rewrite x24{x}^{2}-4 in the form a2b2{a}^{2}-{b}^{2}, where a=xa=x and b=2b=2.
4(x222)4({x}^{2}-{2}^{2})

5
Use Difference of Squares: a2b2=(a+b)(ab){a}^{2}-{b}^{2}=(a+b)(a-b).
4(x+2)(x2)4(x+2)(x-2)

Done

How can we make this solution more helpful?