Algebra 1

Published by Prentice Hall
ISBN 10: 0133500403
ISBN 13: 978-0-13350-040-0

Chapter 12 - Data Analysis and Probability - 12-1 Organizing Data Using Matrices - Practice and Problem-Solving Exercises - Page 718: 30

Answer

$x=-2$ $y=5$

Work Step by Step

For the equation below to be true, the corresponding numbers in the first two matrices added together must equal corresponding number in the final matrix. Lets use: $x+4y=18$ $2x+y=1$ solve for y with the second equation: $ y=1-2x$ Substitute the equation for y into the first equation: $x+4(1-2x) = 18$ Then solve for x: $x+4(1-2x) = 18$ $x+4-8x=18$ $4-8x+x=18$ $4-7x=18$ $-7x=18-4$ $-7x=14$ $x=\frac{14}{-7} =-2$ Now substitute -2 in place of x in the second equation to find y: $ y=1-2x$ $y=1-2(-2)$ $y= 1+4$ $y=5$
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.