Which elementary row operation will reduce the x–element in row 2 to 0 in this matrix?
1 1 1|12
2 1 0|14
2 0 3|19

Respuesta :

Multiply the FIRST row by -2:  -2  -2  -2  |  -24

Now add this result to the 2nd row.  Voila!  You'll end up with a 0 x-element in row 2.

Answer:

[tex]\text{The operation is }R_2\rightarrow R_2-R_3[/tex]            

Step-by-step explanation:

Given the matrix

[tex]\begin{bmatrix}1&1&1\\2&1&0 \\2&0&3\end{bmatrix}[/tex]

An elementary row operations are the operations apply in matrix which includes multiply each element in a row by a non-zero number, Multiply a row by a non-zero number and add the result to another row.

These are used to convert the matrix in echelon form.

Here we have to reduce the x–element in row 2 to 0 in the matrix.

[tex]\begin{bmatrix}1&1&1\\2&1&0 \\2&0&3\end{bmatrix}[/tex]

[tex]R_2\rightarrow R_2-R_3[/tex]

[tex]\begin{bmatrix}1&1&1\\0&1&-3 \\2&0&3\end{bmatrix}[/tex]

The operation will be

[tex]R_2\rightarrow R_2-R_3[/tex]

[tex]2\rightarrow 2-2=0[/tex]

[tex]\text{Hence, the operation is }R_2\rightarrow R_2-R_3[/tex]