Precalculus (10th Edition)

Published by Pearson
ISBN 10: 0-32197-907-9
ISBN 13: 978-0-32197-907-0

Chapter 11 - Systems of Equations and Inequalities - 11.2 Systems of Linear Equations: Matrices - 11.2 Assess Your Understanding - Page 731: 46

Answer

Consistent Solutions set: $\left\{\left(2,-3\right)\right\}$

Work Step by Step

We are given the system of equations: $\begin{cases} \frac{1}{2}x+y=-2\\ x-2y=8 \end{cases}$ Write the augmented matrix: $\begin{bmatrix} \frac{1}{2}&1&|&-2\\1&-2&|&8\end{bmatrix}$ Perform row operations to bring the matrix to the reduced row echelon form: $R_1=2r_1$ $\begin{bmatrix} 1&2&|&-4\\1&-2&|&8\end{bmatrix}$ $R_2=-r_1+r_2$ $\begin{bmatrix}1&2&|&-4\\0&-4&|&12\end{bmatrix}$ $R_2=-\dfrac{1}{4}r_2$ $\begin{bmatrix}1&2&|&-4\\0&1&|&-3\end{bmatrix}$ $R_1=-2r_2+r_1$ $\begin{bmatrix}1&0&|&2\\0&1&|&-3\end{bmatrix}$ Write the corresponding system of equations: $\begin{cases} 1x+0y=2\\ 0x+1y=-3 \end{cases}$ $\begin{cases} x=2\\ y=-3 \end{cases}$ The system is consistent. The solution set is: $\left\{\left(2,-3\right)\right\}$
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.