SOLUTION: Solve: use the Gausd-Jordan elimination (RREF) -3 1 -1 4 2 -1 1 -8 4 -3 2 12

Algebra ->  Matrices-and-determiminant -> SOLUTION: Solve: use the Gausd-Jordan elimination (RREF) -3 1 -1 4 2 -1 1 -8 4 -3 2 12      Log On


   

Question 1140945: Solve: use the Gausd-Jordan elimination (RREF)
-3 1 -1 4
2 -1 1 -8
4 -3 2 12
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Your matrix


Make the pivot in the 1st column by dividing the 1st row by -3:



Eliminate the 1st column:




Make the pivot in the 2nd column by dividing the 2nd row by -1%2F3:





Eliminate the 2nd column:


Find the pivot in the 3rd column in the 3rd row (inversing the sign in the whole row)



Eliminate the 3rd column:



Solution set:
x%5B1%5D+=+4
x%5B2%5D+=+-28
x%5B3%5D+=+-44