View Full Version : Completing the square
jenny54080
Dec 5, 2006, 08:50 AM
3x^2 + x - 1/2 =0
I just don't understand. I know I have to move the 1/2 to the right but how do I divide by 3?
Capuchin
Dec 5, 2006, 08:58 AM
Hi, you can easily divide by 3, don't be afraid to use fractions
Here is a useful walkthrough for completing the square http://www.purplemath.com/modules/sqrquad.htm
galactus
Dec 5, 2006, 09:15 AM
When completing the square, it helps to know the following formula. It expedites matters, rather than going through the steps.
a(x+(b/(2a)))^2+c-(b^2/(4a))
In your case, a=3, b=1, c=-1.2
asterisk_man
Dec 5, 2006, 01:39 PM
Hi, you can easily divide by 3, don't be afraid to use fractions
:rolleyes: nice
acvasagam
Jun 30, 2007, 11:43 PM
Hi, I have one metod to tell you (if you are afraid of using fractions)
3x^2 + x - 1/2 =0
multiply the left and the right by 2 so that 1/2 gets eliminated
6x^2+2x-1=0
now just go with your usual method...