Question

Factor this completely

Answer 1

28n^4 +16n^3 -80n^2  

we can factor out a 4n^2

4n^2 (7n^2 +4n - 20)

4n^2 (7n-10) (n+2)

Answer 2

Answer:

4n^2(7n - 10)(n + 2)

Step-by-step explanation:

The first step in factoring is to try to factor out a common factor.

28n^4 + 16n^3 - 80n^2 =

The GCF of all terms is 4n^2, so we factor out 4n^2.

= 4n^2(7n^2 + 4n - 20)

Now we need to factor the quadratic trinomial.

We can use the ac method.

Multiply ac = 7 * (-20) = -140

We need two factors of -140 that multiply to 4.

The factors are -10 and 14.

We rewrite the middle term, 4n as 14n - 10n.

= 4n^2(7n^2 + 14n - 10n - 20)

Now we factor by parts.

= 4n^2[7n(n + 2) -10(n + 2)]

= 4n^2(7n - 10)(n + 2)