Question

multiply using a special product formula.
(9x - 8)(9x + 8)
(9x - 8)(9x + 8) = \square (simplify your answer.)

Explanation:

Step1: Recognize difference of squares

The expression is of the form $(a-b)(a+b)$, which equals $a^2 - b^2$. Here, $a=9x$, $b=8$.

Step2: Calculate $a^2$

$a^2 = (9x)^2 = 81x^2$

Step3: Calculate $b^2$

$b^2 = 8^2 = 64$

Step4: Substitute into the formula

$a^2 - b^2 = 81x^2 - 64$

Answer:

$81x^2 - 64$