Question

Yasin performs the elementary row operation represented by R2 - ½ R1 on matrix A.

Answer 1

We are given a matrix of

$\begin{bmatrix}{4} & {3} & {0} \\ {-6} & {-3} & {12} \\ {} & {} & \end{bmatrix}$

Yasin performs R2 - 1/2R1

The second row and column will be

For the first row

-6 - 1/2(4)

-6 - 2

= -8

For the second row

-3 - 1/2(3)

= -3 -3/2

= -2 * 3 / 1 - 3 x 2 / 2 / 2

= -6 - 3 / 2

= -9/2

Third row

12 - 1/2(0)

= 12 - 0

12

The new matrix is

$\begin{bmatrix}{4} & {3} & {0} \\ {-8} & {-\frac{9}{2}} & {12} \\ {} & {} & {}\end{bmatrix}$