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Hello, I need some assistance with this precalculus question, please?HW Q8

Hello, I need some assistance with this precalculus question, please?HW Q8-example-1
User Daniel Mann
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1 Answer

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8 votes

STEP - BY - STEP EXPLANATION

What to find?

• The system of equation of the argumented matrix.

,

• The resultant after the given row operations.

Given:

The system of equation is:

7x - 7y + z = -5

3x - 3y + 8z = -5

-6x + y + 3z = 7

Hence, the correct option is D

The following row operations are to be performed;


\begin{gathered} R_1=-2r_2+r_1 \\ \\ R_3=2r_2+r_3 \end{gathered}

The first row operation implies that you will multiply row 2 by -2 and then add to row. The resultant gives a new row 1.

This means that the elements in row 1 becomes:

Row 1 : 1 -1 - 15 | 5

Row 2: 3 -3 8 | -5

As for row 3, we will multiply row 2 by 2 and then add to row 3 to get a new row 3.

That is;

Row 3 : 0 -5 19 | -3

ANSWER

Option D

Part B


\begin{bmatrix}{1} & {-1} & {-15\text{\mid}} & {5} \\ {3} & {-3} & {8\text{ }}| & {-5} \\ 0{} & -5{} & {19\text{ }|} & {-3} \\ {\placeholder{⬚}} & {\placeholder{⬚}} & {\placeholder{⬚}} & {\placeholder{⬚}}\end{bmatrix}

1 -1 - 15 | 5

3 -3 8 | -5

0 -5 19 | -3

Hello, I need some assistance with this precalculus question, please?HW Q8-example-1
Hello, I need some assistance with this precalculus question, please?HW Q8-example-2
User Launchpadmcquack
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