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: 24

Answer

Infinitely many solutions: dependent equations.

Work Step by Step

The given system of equations is $3x-6y=1$ $2x-4y=2/3$ The augmented matrix is $\Rightarrow \left[\begin{array}{cc|c} 3 & -6 & 1\\ 2 & -4 & 2/3 \end{array}\right]$ Perform $R_1\rightarrow \frac{R_1}{3}$. $\Rightarrow \left[\begin{array}{cc|c} 3/3 & -6/3 & 1/3\\ 2 & -4 & 2/3 \end{array}\right]$ Simplify. $\Rightarrow \left[\begin{array}{cc|c} 1 & -2 & 1/3\\ 2 & -4 & 2/3 \end{array}\right]$ Perform $R_2\rightarrow R_2-2\times R_1$. $\Rightarrow \left[\begin{array}{cc|c} 1 & -2 & 1/3\\ 2-2\times 1 &- 4-2\times (-2) & 2/3-2\times (1/3) \end{array}\right]$ Simplify. $\Rightarrow \left[\begin{array}{cc|c} 1 & -2 & 1/3\\ 0 & 0 & 0 \end{array}\right]$ Use back substitution to solve the linear system. $\Rightarrow (1)x+(-2)y=1/3$ and $\Rightarrow (0)x+(0)y=0$ From the second equation we can say that the system has infinitely many solutions: dependent equations.
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.