Answer
$$2(x + 3)(x - 3)$$
Work Step by Step
We see from the binomial that we can factor out a $2$ from both terms to simplify it:
$$2(x^2 - 9)$$
We see now that we have the difference of two squares, so we use the following formula:
$$A^2 - B^2 = (A + B)(A - B)$$
For this binomial, we take the square root of the leading term $(x^2)$ to get $A = x$ and the square root of the second term $(9)$ to get $B = 3$.
So we now plug these two values into the formula for factoring the binomial:
$$2(x + 3)(x - 3)$$
