# Thread: Need Help With Algebra

1. ## Need Help With Algebra

how do you factor polynomial? such as 3x2 + 2x -18x -12?

2. Originally Posted by E-mac
how do you factor polynomial? such as 3x2 + 2x -18x -12?
we would factor by grouping.

first, rewrite as $\displaystyle 3x^2 - 18x + 2x - 12$

now factor the common terms out of the first two and second two

$\displaystyle 3x(x - 6) + 2(x - 6)$

now factor out the common (x - 6)

$\displaystyle (x - 6)(3x + 2)$

viola!

3. Originally Posted by E-mac
how do you factor polynomial? such as 3x2 + 2x -18x -12?

1. Rewrite and rearrange the question:

$\displaystyle Let y(x)= 3x^2 - 18x + 2x - 12$

$\displaystyle y(x) = 3x^2 - 16x - 12$

2. Use Synthetic Division method;

Let
$\displaystyle x$ at any value (try n error) until you manage to get $\displaystyle y(x)= 0$

in that case, if $\displaystyle x = 6$;

$\displaystyle y(6) = 3(6)^2 - 16(6) -12$

$\displaystyle y(6) = 0$

So
$\displaystyle (y-6)$ is one of the factor, and synthetic division method can start be applied

did u know how to use that method?

4. Originally Posted by Jhevon

viola!

viol means "rape"

It's "voilą"

5. "Viola" is a four-stringed violin-like instrument (in English), maybe he meant it

6. Originally Posted by Moo

viol means "rape"

It's "voilą"

Originally Posted by wingless
"Viola" is a four-stringed violin-like instrument (in English), maybe he meant it
i meant what Moo said haha

my fingers slipped when i typed, ti happens

7. Originally Posted by Jhevon

i meant what Moo said haha

ti happens
tea happens, generally at about 16:00

RonL

8. ti happens... to be a good series of electronic device...

9. i hope you guys know i did the "ti" on purpose...that's why it's italicized