Elementary Linear Algebra 7th Edition

Published by Cengage Learning
ISBN 10: 1-13311-087-8
ISBN 13: 978-1-13311-087-3

Chapter 3 - Determinants - Projects - 1 Stochastic Matrices - Page 141: 3

Answer

$$y=-2, \quad x=1.$$

Work Step by Step

To get the solution by Gauss elimination, we form the augmented matrix $$ \left[ \begin {array}{cccc} 1&-2& 5 \\ 3&1&1 \end {array} \right] . $$ Multiply the first row by $-3$ and adding it to the second row, we get $$ \left[ \begin {array}{cccc} 1&-2& 5 \\ 0&7&-14 \end {array} \right] . $$ By the back substitution we have $$y=-2, \quad x=1.$$
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.