Question

Which products result in a difference of squares? Check all that apply.
(5z + 3)(–5z – 3)
(w – 2.5)(w + 2.5)
(8g + 1)(8g + 1)
(–4v – 9)(–4v + 9)
(6y + 7)(7y – 6)
(p – 5)(p – 5)

Answer 1

Explanation:

The difference of squares is given by the form:

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

So we need to take a look at the option and determine the expressions that meet this requirements. So we can conclude that the correct options are:

$\bullet \ (w - 2.5)(w + 2.5) \\ \\ \\ \bullet \ (-4v - 9)(-4v + 9): \\ \\ Rewriting: \\ \\ -(4v+9)(-4v+9) \\ \\ -(9-4v)(9+4v)$