6 Simultaneous equations with 6 Unknowns

Please can someone help me with a MATLAB program that can solve 6 simultaneous euations with 6 unknowns using either crammer's rule or gauss elimination method. Thanks

 Accepted Answer

the cyclist
the cyclist on 18 Jan 2012
Edited: John Kelly on 26 Feb 2015
I think you probably want to use the mldivide operator.

2 Comments

Dear Matlabers,
I have a similar question. Let`s assume the equations as below:
SN = rnd(5,1); a = SN(1); b = SN(2); c = SN(3); d = SN(4); e = SN(5); f = SN(6);
eq1 = a*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(1)^2)*(x(4)^2)-2*x(1)*(x(4)^2)+(x(4)^2)-(2*x(1)*x(4)*x(5))+(x(4)*x(5))+(x(5)^2)) == 0;
eq2 = b*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(1)^2)*(x(4)^2)+(2*x(1)*x(4)*x(5))+(x(5)^2)) == 0;
eq3 = c*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(4)^2)+(2*x(4)*x(5))+(x(5)^2)) == 0;
eq4 = d*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(1)^2)*(x(4)^2)-2*x(1)*(x(4)^2)+ (x(4)^2)-(2*x(1)*x(4)*x(5))-(x(4)*x(5))+(x(5)^2)) == 0;
eq5 = e*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(1)^2)*(x(4)^2)-(2*x(1)*x(4)*x(5))+(x(5)^2)) == 0;
eq6 = f*((x(1)^2)*(x(2)^2)+(x(1)^2)*(x(3)^2)-2*x(1)*(x(2)^2)+(x(2)^2))-((x(4)^2)-(2*x(4)*x(5))+(x(5)^2)) == 0;
here, a,b,c,d,e,f are numbers (0.43 for example). For now I consider them as SN(i):
I want to find x(1),...,x(5) values.
I have tried many ways but no solution was found.
Would you mind to help me with my problem?
Best,
Torsten
Torsten on 12 Apr 2018
Edited: Torsten on 12 Apr 2018
6 equations for 5 unknowns usually gives no solution since the system is overdetermined.

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Asked:

on 18 Jan 2012

Edited:

on 12 Apr 2018

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