How to use one code to solve different system of equations?

I'm new to matlab and I'm absolutely lost of how to work this program. I'm trying to solve three different system of equations with only one code, that computes a row echelon form of any 3x4 matrix and a reduce row echelon form of any 3x4 matrix without using the rref() command. Thank you so much in advance.

The system of equations:

1. 2x1 − 3x2 + x3 = 2

−x1 − x2 + 5x3 = −2

3x1 − 2x2 − x3 = 5

2. −4x2 + 2x3 = 5

−x1 + 3x3 = 2

3x1 − 2x2 = 1

3. −4x2 + x3 = −2

−x1 − x2 + 5x3 = −3

7x1 − 2x2 = −1

[James Tursa]

What have you done so far? What specific problems are you having with your code?

[Stephen23]

Original question by Rachel trent, recovered from Google Cache:

"How to use one code to solve different system of equations?"

I'm new to matlab and I'm absolutely lost of how to work this program. I'm trying to solve three different system of equations with only one code, that computes a row echelon form of any 3x4 matrix and a reduce row echelon form of any 3x4 matrix without using the rref() command. Thank you so much in advance.

The system of equations:

1. 2x1 − 3x2 + x3 = 2

−x1 − x2 + 5x3 = −2

3x1 − 2x2 − x3 = 5

2. −4x2 + 2x3 = 5

−x1 + 3x3 = 2

3x1 − 2x2 = 1

3. −4x2 + x3 = −2

−x1 − x2 + 5x3 = −3

7x1 − 2x2 = −1

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Anirudh Singh]

Create augumanted matrix (A) form the euqation , then use following code :

function A = row_echelon(A)
    [m,n]=size(A);
    for j=1:min(m,n)
        A(j,:) = A(j,:)/A(j,j);
        for i = j+1:m
            A(i,:)= A(i,:)- A(j,:)*A(i,j);
        end
    end
end

Note : This code does not work when A(j,j)=0, So try to madify logic in this code according to your requirements.