# How do you factor the expression #x^4+216x#?

##### 1 Answer

Dec 21, 2015

Factor out the common factor and then look for a familiar form.

Answer is :

#### Explanation:

Factoring :

Always look for a common factor, here it's an

Lucky for us, 216 is a perfect cube:

So it's a sum of cubes and we can use the formula:

You can check that the last quadratic doesn't factor.

/ powered by dansmath \