College Algebra (6th Edition)

Published by Pearson
ISBN 10: 0-32178-228-3
ISBN 13: 978-0-32178-228-1

Chapter 6 - Matrices and Determinants - Exercise Set 6.1 - Page 600: 34

Answer

Solution set: $\{ ( 2$ , $0$ , $-1 ) \}$

Work Step by Step

$\left[\begin{array}{lllll} 3 & 2 & 3 & | & 3\\ 4 & -5 & 7 & | & 1\\ 2 & 3 & -2 & | & 6 \end{array}\right]\left\{\begin{array}{l} \leftarrow R_{1}-R_{3}.\\ .\\ . \end{array}\right.$ $\left[\begin{array}{lllll} 1 & -1 & 5 & | & -3\\ 4 & -5 & 7 & | & 1\\ 2 & 3 & -2 & | & 6 \end{array}\right]\left\{\begin{array}{l} .\\ \leftarrow(-4R_{1}+R_{2}).\\ \leftarrow(-2R_{1}+R_{3}). \end{array}\right.$ $\left[\begin{array}{lllll} 1 & -1 & 5 & | & -3\\ 0 & -1 & -13 & | & 13\\ 0 & 5 & -12 & | & 12 \end{array}\right]\left\{\begin{array}{l} .\\ \times(-1).\\ \leftarrow(5R_{2}+R_{3}). \end{array}\right.$ $\left[\begin{array}{lllll} 1 & -1 & 5 & | & -3\\ 0 & 1 & 13 & | & -13\\ 0 & 0 & -77 & | & 77 \end{array}\right]\left\{\begin{array}{l} .\\ .\\ \Rightarrow z=-1. \end{array}\right.$ Back substitute into row/equation 2, $y+13(-1)=-13$ $y=-13+13=0$ Back substitute into row/equation 1: $x-(0)+5(-1)=-3$ $x=-3+5=2$ Solution set: $\{ ( 2$ , $0$ , $-1 ) \}$
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.