Algebra: A Combined Approach (4th Edition)

Published by Pearson
ISBN 10: 0321726391
ISBN 13: 978-0-32172-639-1

Chapter 9 - Section 9.2 - Solving Systems of Equations Using Matrices - Exercise Set - Page 647: 9

Answer

\( x = -2 \), \( y = 5 \), \( z = -2 \)

Work Step by Step

Taking our equations into matrix form: \[ \begin{bmatrix} 1 & 1 & 0 & 3 \\ 0 & 2 & 0 & 10 \\ 3 & 2 & -4 & 12 \end{bmatrix} \] 1. Divide \( \text{row 2} \) by 2: \[ \begin{bmatrix} 1 & 1 & 0 & 3 \\ 0 & 1 & 0 & 5 \\ 3 & 2 & -4 & 12 \end{bmatrix} \] 2. Subtract \( \text{row 2} \) from \( \text{row 1} \) and \( 2 \times \text{row 2} \) from \( \text{row 3} \): \[ \begin{bmatrix} 1 & 0 & 0 & -2 \\ 0 & 1 & 0 & 5 \\ 3 & 0 & -4 & 2 \end{bmatrix} \] 3. Subtract \( 3 \times \text{row 1} \) from \( \text{row 3} \): \[ \begin{bmatrix} 1 & 0 & 0 & -2 \\ 0 & 1 & 0 & 5 \\ 0 & 0 & -4 & 8 \end{bmatrix} \] 4. Divide \( \text{row 3} \) by \(-4\): \[ \begin{bmatrix} 1 & 0 & 0 & -2 \\ 0 & 1 & 0 & 5 \\ 0 & 0 & 1 & -2 \end{bmatrix} \]
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.