Intermediate Algebra (12th Edition)

Published by Pearson
ISBN 10: 0321969359
ISBN 13: 978-0-32196-935-4

Chapter 3 - Section 3.1 - Systems of Linear Equations in Two Variables - 3.1 Exercises: 28


$x=-1$ $y=3$

Work Step by Step

First, we have to solve the second equation for $y$ and after that, we can substitute this expression in the first equation: $4+7x=-y$ $-4-7x=y$ $6x-y=-9$ $6x-(-4-7x)=13x+4=-9$ $13x=-13$ $x=-1$ $-4-7x=-4-7(-1)=3=y$ We need to check, if it is the right solution, we substitute x with $-1$ and y with $3$: $6(-1)-3=-9$ $\checkmark$ $4+7(-1)=-3$ $\checkmark$
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.