Answer
$(4x + 9)(4x - 9)$
Work Step by Step
This expression looks like it could be factored as the difference of two squares. Use the following steps to determine this:
1. Check to see if the first and last terms are perfect squares:
Take the square root of the first term:
$\sqrt {16x^2} = 4x$
Take the square root of the last term:
$\sqrt {81} = 9$
2. The formula for factoring the difference of two squares is the following:
$a^2 - b^2 = (a + b)(a - b)$
In this exercise, $a = 4x$ and $b = 9$.
3. Write the expression in polynomial in factored form:
$(4x + 9)(4x - 9)$
