# How do you factor completely #−7x^2 + 14x − 21#?

##### 1 Answer

May 18, 2016

#### Explanation:

f(x) = -7y = -7(x^2 - 2x + 3)

D = d^2 = b^2 - 4ac = 4 - 12 = -8.

Since D < 0, the trinomial in parentheses can't be factored.

Therefor:

NOTE. We can factor f(x) by using the 2 complex roots.

The factored form will be: