# Factorization help

• Jan 30th 2010, 02:08 PM
22upon7
Factorization help
Hi everybody,

I can't seem to work out how to factorize this particualar sum. Could someone please explain how you go through it?

The sum is:

\$\displaystyle 10(2x+y)^2+11(2x+y)-6\$

My book gives this as the answer, although I don't know how to get there:

\$\displaystyle (10x+5y-2)(4x+2y+3)\$

Any help would be much appreciated,

Thanks!

Drew
• Jan 30th 2010, 02:10 PM
VonNemo19
Quote:

Originally Posted by 22upon7
Hi everybody,

I can't seem to work out how to factorize this particualar sum. Could someone please explain how you go through it?

The sum is:

\$\displaystyle 10(2x+y)^2+11(2x+y)-6\$

My book gives this as the answer, although I don't know how to get there:

\$\displaystyle (10x+5y-2)(4x+2y+3)\$

Any help would be much appreciated,

Thanks!

Drew

Let \$\displaystyle u=2x+y\$. Can you factor \$\displaystyle 10u^2+11u-6\$?
• Jan 30th 2010, 02:18 PM
22upon7
Quote:

Originally Posted by VonNemo19
Let \$\displaystyle u=2x+y\$. Can you factor \$\displaystyle 10u^2+11u-6\$?

Yes I can, that makes it much easier, thanks a lot!
• Jan 30th 2010, 02:21 PM
VonNemo19
Quote:

Originally Posted by 22upon7
Yes I can, that makes it much easier, thanks a lot!

Don't forget to back substitute. (Hi)