Intermediate Algebra for College Students (7th Edition)

Published by Pearson
ISBN 10: 0-13417-894-7
ISBN 13: 978-0-13417-894-3

Chapter 3 - Section 3.4 - Matrix Solutions to Linear Systems - Exercise Set - Page 229: 13

Answer

The answer is $\left[\begin{array}{ccc|c} 1& 1 & -1&6 \\ 0 &-3 &3&-15 \\ 0&-4&2&-14\\ \end{array}\right]$.

Work Step by Step

The given matrix is $\left[\begin{array}{ccc|c} 1& 1 & -1&6 \\ 2 &-1 &1&-3 \\ 3&-1&-1&4\\ \end{array}\right]$ Perform $ -2R_1+R_2 $ and $ -3R_1+R_3 $ Multiply row one by $-2 $ and add to row two. Multiply row one by $ -3 $ and add to row three. $\left[\begin{array}{ccc|c} 1& 1 & -1&6 \\ -2 \cdot 1+2 &-2 \cdot 1-1 &-2 \cdot (-1)+1&-2 \cdot (6)-3 \\ -3\cdot 1+3&-3\cdot 1-1&-3\cdot (-1)-1&-3\cdot (6)+4\\ \end{array}\right]$ Simplify. $\left[\begin{array}{ccc|c} 1& 1 & -1&6 \\ -2 +2 &-2 -1 &2+1&-12-3 \\ -3+3&-3-1&3-1&-18+4\\ \end{array}\right]$ $\left[\begin{array}{ccc|c} 1& 1 & -1&6 \\ 0 &-3 &3&-15 \\ 0&-4&2&-14\\ \end{array}\right]$.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.