# Probably a simple question/factoring by and old guy

• Oct 25th 2009, 01:14 PM
jonb
Probably a simple question/factoring by and old guy
Someone asked me to help them do something that I have not done in 25 years at least and they have no book.

Sorry I don't know how to do math symbols on a computer.

2xsquare+7x-4

This looks like it should be easy but I can't figure out how to factor it so I can't help this person.
Thanks
Jon
• Oct 25th 2009, 01:20 PM
e^(i*pi)
Quote:

Originally Posted by jonb
Someone asked me to help them do something that I have not done in 25 years at least and they have no book.

Sorry I don't know how to do math symbols on a computer.

2xsquare+7x-4

This looks like it should be easy but I can't figure out how to factor it so I can't help this person.
Thanks
Jon

\$\displaystyle 2x^2+7x-4 =(2x-1)(x+4)\$
• Oct 25th 2009, 01:25 PM
pickslides
\$\displaystyle 2x^2 +7x-4\$ factors to the form \$\displaystyle (2x+a)(x+b)\$ where \$\displaystyle a\$ and \$\displaystyle b\$ multiply together to give \$\displaystyle -4\$

Try some combinations by expanding \$\displaystyle (2x+a)(x+b)\$ that gives you \$\displaystyle 2x^2 +7x-4\$

Spoiler:

\$\displaystyle (2x-1)(x+4)\$
• Oct 25th 2009, 01:32 PM
jonb
thanks a bunch