Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

Published by Pearson
ISBN 10: 0-32193-104-1
ISBN 13: 978-0-32193-104-7

Chapter 10 - Systems of Equations and Inequalities - Section 10.2 Systems of Linear Equations: Matrices - 10.2 Assess Your Understanding - Page 749: 22

Answer

$\left[\begin{array}{ccc|c} {1}&{-3}&{-4}&{-6}\\ {6}&{-5}&{6}&{-6}\\ {0}&{-2}&{0}&{0}\end{array}\right]$

Work Step by Step

The standard form of a linear equation can be expressed as: $a_{i1}x_{1}+a_{i2}x_{2}+...+a_{in}x_{n}=b_{i}$ where, the index $i$ indicates that it is the i-th equation of a system of equations. In order to write the augmented matrix $[A|B]$ of a system of equations in standard form, we must follow some important points: 1. To express a system in matrix form, we must extract the coefficients of the variables and constants. 2. Draw a vertical line to separate the coefficient entries from the constants (essentially replacing the equal signs). 3. The entries of the coefficient matrix $A=[a_{ij}]$ must be placed to the left of the line. 4. The constants of $B=[b_{i}]$ must be placed to the right of the line. We can write the system as an augmented matrix $[A|B]$ as follows: $\left\{\begin{array}{llll} x & -3y & -4z & =-6\\ 26x & -5y & +6z & =-6\\ -x & +y & +4z & =6 \end{array}\right.\rightarrow\left[\begin{array}{ccc|c} {1}&{-3}&{-4}&{-6}\\ {6}&{-5}&{6}&{-6}\\ {-1}&{1}&{4}&{6}\end{array}\right]$ We perform the row operation as: $R_{2}=-6r_{1}+r_{2}$ $R_{3}=r_{1}+r_{3}$ $=\left[\begin{array}{ccc|c} {1} &{-3} &{-4} &{-6}\\ {-6(1)+6}&{-6(-3)-5}&{(-6)(-4)+6}&{-6(-6)-6}\\ {1-1} &{(-3)+1} &{(-4)+4} &{0}\end{array}\right]$ $=\left[\begin{array}{ccc|c} {1}&{-3}&{-4}&{-6}\\ {6}&{-5}&{6}&{-6}\\ {0}&{-2}&{0}&{0}\end{array}\right]$
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.