# How do you factor the expression #x^4 +6x ^2-7#?

##### 1 Answer

Nov 29, 2016

#### Explanation:

Notice that the sum of the coefficients is

#1+6-7 = 0#

Hence

So

#x^4+6x^2-7 = (x^2-1)(x^2+7) = (x-1)(x+1)(x^2+7)#

The remaining quadratic factor has no linear factors with Real coefficients.

If you use Complex numbers then it can be factored as:

#x^2+7 = (x-sqrt(7)i)(x+sqrt(7)i)#

but I would guess that you do not want to do that at Algebra 1 level.