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Perform the indicated row operations, then write the new matrix.

1 -1 -2 3 53 3 2 41 2R1 R2R2
-3R1 R3R3
a. 1 -1 0 5 73
b. 1 -1 -2 3 53
c. 1 1 -1 0 5 7 1 0 1 14
d. 0 5 7 1 3 2 4 1

2 Answers

8 votes

Answer:

Explanation:

:)

Perform the indicated row operations, then write the new matrix. 1 -1 -2 3 53 3 2 41 2R-example-1
User Osbert
by
4.6k points
7 votes

The matrix is not properly formatted.

However, I'm able to rearrange the question as:


\left[\begin{array}{ccc}1&1&1|-1\\-2&3&5|3\\3&2&4|1\end{array}\right]

Operations:


2R_1 + R_2 ->R_2


-3R_1 +R_3 ->R_3

Please note that the above may not reflect the original question. However, you should be able to implement my steps in your question.

Answer:


\left[\begin{array}{ccc}1&1&1|-1\\0&5&7|1\\0&-1&1|4\end{array}\right]

Explanation:

The first operation:


2R_1 + R_2 ->R_2

This means that the new second row (R2) is derived by:

Multiplying the first row (R1) by 2; add this to the second row

The row 1 elements are:


\left[\begin{array}{ccc}1&1&1|-1\end{array}\right]

Multiply by 2


2 * \left[\begin{array}{ccc}1&1&1|-1\end{array}\right] = \left[\begin{array}{ccc}2&2&2|-2\end{array}\right]

Add to row 2 elements are:
\left[\begin{array}{ccc}-2&3&5|3\end{array}\right]


\left[\begin{array}{ccc}2&2&2|-2\end{array}\right] + \left[\begin{array}{ccc}-2&3&5|3\end{array}\right]


\left[\begin{array}{ccc}0&5&7|1\end{array}\right]

The second operation:


-3R_1 +R_3 ->R_3

This means that the new third row (R3) is derived by:

Multiplying the first row (R1) by -3; add this to the third row

The row 1 elements are:


\left[\begin{array}{ccc}1&1&1|-1\end{array}\right]

Multiply by -3


-3 * \left[\begin{array}{ccc}1&1&1|-1\end{array}\right] = \left[\begin{array}{ccc}-3&-3&-3|3\end{array}\right]

Add to row 2 elements are:
\left[\begin{array}{ccc}3&2&4|1\end{array}\right]


\left[\begin{array}{ccc}-3&-3&-3|3\end{array}\right] + \left[\begin{array}{ccc}3&2&4|1\end{array}\right]


\left[\begin{array}{ccc}0&-1&1|4\end{array}\right]

Hence, the new matrix is:


\left[\begin{array}{ccc}1&1&1|-1\\0&5&7|1\\0&-1&1|4\end{array}\right]

User Murakami
by
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