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mclovin92
Mar 6, 2010, 03:36 PM
I need help with this system of 4 x 4 system of equations:

2a-6b+4c-6d=-12
4a+6b-c+2d=25
2a+8c-6d=-12
2a+6b-3c+d=17

FadedMaster
Mar 6, 2010, 03:42 PM
Is there any methods you have already tried? If you've already attempted the problem, you will probably benefit better from any help by posting any attempts you have made.

Also, is there a specific method that you are to be using? There's a few ways to solve for those variables.

mclovin92
Mar 6, 2010, 03:44 PM
I have made a few attempts and am absolutely stumped . I just somewhere to start from

FadedMaster
Mar 6, 2010, 03:48 PM
i have made a few attempts and am absolutely stumped . i just somewhere to start from

What method of solving systems of equations are you practicing right now?

If you're using substitution, then that problem gets pretty messy. If you're supposed to use addition (adding each equation to one another), then it's a little more manageable.

This page may help with either of those: Algebra II: Systems of Equations and Inequalities - Math for Morons Like Us (http://library.thinkquest.org/20991/alg2/systems.html)

The middle section deals with using addition. That is the method I would use to solve that one, unless your teacher wants you practicing substitution.

EDIT: Oh yeah, I forgot about Gaussian elimination too (http://www.purplemath.com/modules/systlin6.htm).

mclovin92
Mar 6, 2010, 03:55 PM
I am allowed to use either method

mclovin92
Mar 6, 2010, 06:00 PM
What method of solving systems of equations are you practicing right now?

If you're using substitution, then that problem gets pretty messy. If you're supposed to use addition (adding each equation to one another), then it's a little more manageable.

This page may help with either of those: Algebra II: Systems of Equations and Inequalities - Math for Morons Like Us (http://library.thinkquest.org/20991/alg2/systems.html)

The middle section deals with using addition. That is the method I would use to solve that one, unless your teacher wants you practicing substitution.

EDIT: Oh yeah, I forgot about Gaussian elimination too (Systems of Linear Equations: Gaussian Elimination (http://www.purplemath.com/modules/systlin6.htm)).

I used that link but it doesn't talk about using problems w 4 equations and variables

KISS
Mar 6, 2010, 06:36 PM
You can also use determinents.