Question

What is the form of the Difference of Squares identity?O A. a? - b - (a - b)(a - b)B. 22 - 62 = (a + b)(a + b)C. 22 - 61 = (a + b)(a - b)D. 3° +6+ = (2-b)(a - b)

Answer 1

The difference of squares identity can be expressed as

$a^2-b^2=(a-b)(a+b)$

this is because when expanding the expression on the left the term ab needs to be cancelled like this

$\begin{gathered} (a-b)(a+b)=a\cdot a+a\cdot b-a\cdot b-b\cdot b \\ =a^2+ab-ab-b^2 \\ =a^2-b^2 \end{gathered}$