# Factoring

• Sep 7th 2008, 03:54 PM
Itachi888Uchiha
Factoring
Ok it's 3a squared-2a-21
• Sep 7th 2008, 03:58 PM
mr fantastic
Quote:

Originally Posted by Itachi888Uchiha
Ok it's 3a squared-2a-21

\$\displaystyle 3a^2 - 2a - 21 = 3a^2 + 7a - 9a - 21 = \, .....\$
• Sep 7th 2008, 04:00 PM
Itachi888Uchiha
Quote:

Originally Posted by mr fantastic
\$\displaystyle 3a^2 - 2a - 21 = 3a^2 + 7a - 9a - 21 = \, .....\$

Um, no parenthesis?
• Sep 7th 2008, 04:03 PM
11rdc11
\$\displaystyle 3a^2 - 2a - 21\$

=\$\displaystyle 3a^2 - 9a + 7a - 21\$

=\$\displaystyle 3a(a-3) +7(a-3)\$

=\$\displaystyle (3a + 7)(a - 3)\$
• Sep 7th 2008, 04:13 PM
mr fantastic
Quote:

Originally Posted by Itachi888Uchiha
Um, no parenthesis?

The implication of \$\displaystyle = \, .....\$ is that you continue working from where I left off.

The intent is to give you a push in the right direction without spoon feeding the entire solution to you.
• Sep 7th 2008, 04:16 PM
Itachi888Uchiha
Quote:

Originally Posted by mr fantastic
The implication of \$\displaystyle = \, .....\$ is that you continue working from where I left off.

The intent is to give you a push in the right direction without spoon feeding the entire solution to you.

I didn't know what to do at all, and I didn't want to make up a problem because I wouldn't have been sure it worked. Now that, the other dude posted, I remember. It's been a long summer........
• Sep 8th 2008, 12:29 AM
john doe
well id teach you but my answers tend to be wrong

but i think this guy explains it pretty good