Question

simplify the following expression. (6d - 9)(6d + 9) ?d² -

Explanation:

Step1: Identify the formula

The expression \((6d - 9)(6d + 9)\) is in the form of \((a - b)(a + b)\), which follows the difference of squares formula: \((a - b)(a + b)=a^{2}-b^{2}\). Here, \(a = 6d\) and \(b = 9\).

Step2: Apply the difference of squares formula

First, calculate \(a^{2}\): \((6d)^{2}=6^{2}\times d^{2}=36d^{2}\).
Then, calculate \(b^{2}\): \(9^{2} = 81\).
So, \((6d - 9)(6d + 9)=(6d)^{2}-9^{2}=36d^{2}-81\).

Answer:

The first blank is \(36\) and the second blank is \(81\), so the simplified expression is \(36d^{2}-81\).