My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum

Thanks Tree2Thanks
LinkBack Thread Tools Display Modes
August 2nd, 2017, 10:53 AM   #11
Global Moderator
greg1313's Avatar
Joined: Oct 2008
From: London, Ontario, Canada - The Forest City

Posts: 7,745
Thanks: 1001

Math Focus: Elementary mathematics and beyond
Originally Posted by labasa View Post
For example something like 3x^2 + 19x + 6
As 3 has only 1 and 3 as (positive) factors,

3x$^2$ + 19x + 6 = (3x + a)(x + b)

Now find a and b so that a * b = 6 and 3b + a = 19 hold.

Last edited by greg1313; August 2nd, 2017 at 10:56 AM.
greg1313 is online now  
August 2nd, 2017, 11:12 AM   #12
Senior Member
Joined: May 2016
From: USA

Posts: 904
Thanks: 359

Originally Posted by labasa View Post
Just wondering what is the easiest method to factorise ax^2 +bx + c at high school level...
many thanks
Personally, I trying factoring for a minute or so. If I don't see a factoring quickly, I use the method specified in my previous post.

$ax^2 + bx + c = a * \left ( x + \dfrac{b + d}{2a} \right ) \left ( x + \dfrac{b - d}{2a} \right), \text { where } d = \sqrt{b^2 - 4ac}.$
JeffM1 is offline  

  My Math Forum > High School Math Forum > Algebra

curious, factoring, high, school

Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Forum Replies Last Post
Just a little curious and need help with my school probabilities Rlexz Probability and Statistics 5 October 30th, 2015 11:00 AM
high school homework help?? xcortx Physics 1 November 3rd, 2014 05:45 PM
May you please help me with high school calculus? savica Calculus 2 June 17th, 2009 04:42 PM
XYZ HIGH SCHOOL symmetry Algebra 4 May 14th, 2007 08:28 AM

Copyright © 2018 My Math Forum. All rights reserved.