Recall the formula for factoring the difference of two squares: a2 – b2 = (a + b)(a – b) Use the formula to factor n8 – 9. What is the value of a? n n8 n4
To answer your question: Rewrite 81x2 as (9x)2.(9x)2−49Rewrite 49 as 72.(9x)2−72 Both terms are perfect squares, factor using the difference of squares formula, a2−b2=(a+b)(a−b) where a=9x and b=7.(9x+7)(9x−7)
