How do you factor x33x281x+243?

1 Answer
Jun 21, 2016

=(x3)(x+9)(x9)

Explanation:

If an expression has 4 more more terms, group them in pairs (or threes) first - making sure there is + sign between the groups.

(x33x2)+(81x+243) look for a common factor

=x2(x3)81(x3)

Note that -81 was used as a common factor so the sign in the second bracket changed.
=(x3)(x281) difference of squares

=(x3)(x+9)(x9)