Question

2x + y - z = -8

2y + 3z = -6
-1/2x + y + z = -4


For the following matrix, which of the following matrix operations would result in a11 = 1?


Multiply row 2 by -1 and add it to row 1.

Multiply row 1 by - 1/2.

Multiply row 1 by 1/2.

Multiply row 3 by -4 and add it to row 1.

(please show your solution if possible & pls just type in the comments if unsure abt your answer.. thank you)

Answer 1

Multiply row 1 by
`(1)/(2)`.

Explanation:

The augmented matrix of the system of linear equation is described below:

`\left[\begin{array}{cccc}2&1&-1&-8\\0&2&3&-6\\-(1)/(2) &1&1&-4\end{array}\right]`

Where
`a_(11) = 2`, if we need to create
`a_(11) = 1`, we need to multiply row 1 by
`(1)/(2)`, that is to say:

`\left[\begin{array}{cccc}1&(1)/(2) &-(1)/(2) &-4\\0&2&3&-6\\-(1)/(2) &1&1&-4\end{array}\right]`

Hence, the correct answer is: Multiply row 1 by
`(1)/(2)`.