# Homework Help: Solving Quadratic Equation Using Box Factoring

1. Jul 29, 2011

### nordqvist11

1. The problem statement, all variables and given/known data

f(x)=6x^2+9x-6

Where does this function intersect the x-axis (i.e. what are the roots or zeroes of f(x))?

Solve by factoring using the Box Method. When I use the method that is shown on this website http://www.purplemath.com/modules/factquad2.htm for this particular problem I end up with this as my factored down version of the equation.
(6x-3)(3x+6)
But that is wrong because I would end up with 18x^2 as my leading term instead of the 6x^2 (which is in the desired equation) when I FOIL them out.

My question is that does using the method on that website to factor down a quadratic work for this equation? If so, could someone tell me what I'm doing wrong.

Thanks :)

2. Relevant equations

3. The attempt at a solution

Last edited by a moderator: May 5, 2017
2. Jul 29, 2011

### I like Serena

Welcome to PF, nordqvist11!

Your equation looks like the last example on the page you mentioned.
It says there that you should take out the common factor first...

3. Jul 29, 2011

### nordqvist11

You're right it does :). Thanks a lot, I got a real headache because of that.