Week 10 – Difference of squares

This week in math we looked over the difference of squares, a a concept we discovered in week 9 where you use the method as a way of skipping the distributive method while evaluating your expression.

The method works as follows:

(a+b) (a-b)

= a^2 + ab – ba – b^2

= a^2b^2

This can be used to work backwards as well, when factoring expressions.

Example:

75x^2y^2 -3

First we remove the common factor,

3 (25x^2y^2 -1)

Then we factor.

3 (5xy – 1) (5xy + 1)

Leave a Reply

Your email address will not be published. Required fields are marked *