$\"\"$

The system of linear equations are

$\"\"$ (Equation 1)

$\"\"$ (Equation 2)

$\"\"$ (Equation 3) and the row operations are add $\"\"$ times equation 1 to equation 3.

The above system change into equivalent system by using above row operations as follows:

$\"\"$ (Write original equation 2)

$\"\"$ (Multiply first equation by negative 2)

$\"\"$ (Write original equation 3) $\"\"$

Add equation 1 to equation 3:

$\"\"$

Add $\"\"$ times the first equation to the third equation to obtain a new third equation.

So the equivalent system is

$\"\"$ (Equation 1)

$\"\"$ (Equation 2)

$\"\"$ (Equation 3). $\"\"$

The equivalent system is

$\"\"$ (Equation 1)

$\"\"$ (Equation 2)

$\"\"$ (Equation 3)

The second step in putting the system in row - echelon form.