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)
= + ab – ba –
= –
This can be used to work backwards as well, when factoring expressions.
Example:
75 -3
First we remove the common factor,
3 (25 -1)
Then we factor.
3 (5xy – 1) (5xy + 1)