(Solved) Polynomial Factoring?

gaflyc90

wrote...

Go to Answer

Posts: 17

Rep:

9 years ago

Anyone know how to factor polynomials because I am completely stumped? The tutor in our college algebra class yesterday..she wasn't the greatest, lets just put it that way. =) And my home work is due at 4 today, so can someone please help explain it to me. Like:

1.GCF of 8x^4, -24x^2
2.16p^6q^4, 32p^3q^3, -48pq^2
3.Factor: 8x^2-4x-20 (this one confuses me because there are no like terms. What do I do with it???

THANKS!

Read 222 times

4 Replies

Report

Replies

dcgreen

wrote...

9 years ago

1. 8x^2 is GCF
8x^4 and -24x^4
Take the smaller exponent (2) and the GCF of 8 and 24 (8)

2. 16pq^2

3. 4(2x^2 - x - 5)
The trinomial does not factor.

Report

Answer accepted by topic starter

ddmmk

wrote...

Posts: 20

Rep:

9 years ago

Report

Related Topics

len5002

wrote...

9 years ago

1.
GCF of 8x^4, -24x^2 is 24 and x^4

2.
GCF of 16p^6q^4, 32p^3q^3, -48pq^2 is 96 and p^6q^12

3.
8x^2 - 4x - 20
= 4(4x^2 - x - 5)

Report

Leeta c.

wrote...

9 years ago

why don't you use the discriminant method?

So if you have a quadratic expression of the form ax^2 + bx + c and you want to factor it, you take the detla, ? = b^2 - 4ac, then you find the two solution : x1 = (-b - ??)/2a and x2 = (-b + ??)/2a
and then you an write the expression as a(x - x1)(x - x2)

For example, the last one is 8x^2-4x-20
? = 16 - 4*8*(-20) = 656

So x1 = ( -16 - ?656 ) / -8 = -2 - 1/2*?41 and x2 = -2 + 1/2*?41

Thus, 8x^2-4x-20 = 8 (x - (-2 - 1/2*?41)) (x - 2 + 1/2*?41)

** for the second one, 8x^4 - 24x^2 = x^2 (8x^2 - 24) = 8x^2 (x^2 - 3)

Now we factor x^2 - 3 using this identity: a^2 - b^2 = (a - b) (a + b)
In this case, a = x, and b = ?3

Thus 8x^2 - 24 = 8 x^2 ( x - ?3 ) (x + ?3 )

Report

New Topic

Home Search Q & A Board Gallery Resource Library Blog Dictionary Chat	Quick Links Start a Topic Latest Topics Unanswered Questions Courses Study Tools Browse by Textbook	Social Facebook YouTube Community Stats Who's Online Trending Staff	Help About Us Take the Tour Study Tips Posting Guidelines Terms and Policies Contact Us
Biology Forums - Study Force © 2010-2024 \| Powered by SMF \| SMF © 2015, Simple Machines \| Sitemap Biology-Forums.com is not affiliated with any publisher. Book covers, title and author names appear for reference only.