Hi Denise,

Factoring is often a matter of looking at an expression and seeing a pattern, or recognizing something you have seen before. For example the fact that I know twenty-four is six times four is that when I learned my times tables I learned that

6 4 = 24

and I can read it backwards to get

24 = 6 4.

The same is true for a³ - b³ . I know that if I multiply

(a - b)(a² + ab + b²)

I get

(a - b)(a² + ab + b²)
= a³ + a²b + ab² - a² - ab² - b³
= a³ - b³

and I can read it backwards to get

a³ - b³ = (a - b)(a² + ab + b²)

Penny

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