Solving Systems of Linear Equations (Echelon Matrices)

What I did was I put 18 * 16/4 which is 18 * 4 = 72 which is wrong.In summary, the task was to find the general solution of a given system of equations using row echelon operations. The attempt at a solution was shown in a provided image, where the correct answer was given as x = 1, y = 1, z = 2, w = −3. However, a mistake was made when adding 18 times r3 to r4, resulting in an incorrect value for the last term of row 3. The correct value should have been 16/14*18, not 16/4*18.
  • #1
DiamondV
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Homework Statement


find the general solution of the given system of equations:
http://puu.sh/ncKaS/57a333f5b9.png

Homework Equations


Row Echelon Operations

The Attempt at a Solution


http://puu.sh/ncKcm/3e2b2bd5ab.jpg

The correct answer given is x = 1, y = 1, z = 2, w = −3

I have done quite a few of these now around 5-6 and have gotten 3 correct. I don't know what my mistake with this one is. We are using Gaussian elimination.[/B]
 
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  • #2
When you add 18 times r3 to r4, the last term of row 3 is 16/14*18 not 16/4*18
 
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  • #3
Gianmarco said:
When you add 18 times r3 to r4, the last term of row 3 is 16/14*18 not 16/4*18

Ahhh. Thanks soo much.
 

1. What is a system of linear equations?

A system of linear equations is a group of two or more equations that contain two or more variables. The goal is to find the values of the variables that satisfy all of the equations in the system.

2. What is an echelon matrix?

An echelon matrix is a special type of matrix in which the leading coefficient (the first non-zero number) in each row is to the right and below the leading coefficient in the row above it. It is used to solve systems of linear equations by reducing the system to an upper triangular matrix.

3. How do you create an echelon matrix?

To create an echelon matrix, you must use the Gaussian elimination method. This involves performing elementary row operations, such as multiplying a row by a non-zero constant or adding a multiple of one row to another, to manipulate the matrix until it is in echelon form.

4. Can an echelon matrix have more than one solution?

Yes, an echelon matrix can have multiple solutions. This occurs when one or more variables have no unique value and can take on any value. These are known as free variables and are represented by a parameter in the solution.

5. Are there any special cases when solving systems of linear equations with echelon matrices?

Yes, there are two special cases to consider when solving systems of linear equations with echelon matrices. The first is when the matrix has no solutions, which occurs when the echelon form has a row of all zeros except for the last column. The second is when the matrix has infinitely many solutions, which occurs when all the rows in the echelon form are nonzero and the last column is all zeros.

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