SOLUTION: Use determinate method to solve 2x+3y-4z=-4 x-2y+2z=3 x+3y-2z=1

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Question 1179993: Use determinate method to solve
2x+3y-4z=-4
x-2y+2z=3
x+3y-2z=1

Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
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Your matrix

        X1	X2	X3	b
1	2	3	-4	-4
2	1	-2	2	3
3	1	3	-2	1


Write down the main matrix and find its determinant

        X1	X2	X3
1	2	3	-4
2	1	-2	2
3	1	3	-2

Δ = -12


Replace the 1st column of the main matrix with the solution vector and find its determinant

        X1	X2	X3
1	-4	3	-4
2	3	-2	2
3	1	3	-2

Δ1 = -12


Replace the 2nd column of the main matrix with the solution vector and find its determinant

       X1	X2	X3
1	2	-4	-4
2	1	3	2
3	1	1	-2

Δ2 = -24


Replace the 3rd column of the main matrix with the solution vector and find its determinant

        X1	X2	X3
1	2	3	-4
2	1	-2	3
3	1	3	1

Δ3 = -36


x1 = Δ1 / Δ = (-12) / (-12) = 1
x2 = Δ2 / Δ = (-24) / (-12) = 2
x3 = Δ3 / Δ = (-36) / (-12) = 3


Solution set:

x1 = 1
x2 = 2
x3 = 3

Solved.

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On Cramer's rule for solving systems of 3 equations in 3 unknowns see the lessons
    - Determinant of a 3x3 matrix
    - Co-factoring the determinant of a 3x3 matrix
    - HOW TO solve system of linear equations in three unknowns using determinant (Cramer's rule)
    - Solving systems of linear equations in three unknowns using determinant (Cramer's rule)
    - Solving word problems by reducing to systems of linear equations in three unknowns
in this site.


Also, you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic
     "3x3-Matrices, determinants, Cramer's rule for systems in three unknowns"


In addition, there are many free of charge SOLVERS on a Cramer's rule in the internet.

One of such popular solvers is in this site under the link
https://www.algebra.com/algebra/homework/Matrices-and-determiminant/cramers-rule-3x3.solver

https://www.algebra.com/algebra/homework/Matrices-and-determiminant/cramers-rule-3x3.solver