Thinking Mathematically (6th Edition)

Published by Pearson
ISBN 10: 0321867327
ISBN 13: 978-0-32186-732-2

Chapter 7 - Algebra: Graphs, Functions, and Linear Systems - Chapter Summary, Review, and Test - Review Exercises - Page 481: 36

Answer

See below:

Work Step by Step

In each equation in the system, find the intercepts. Consider the first equation, \[2x-y=-1\] \[y\text{-intercept}\]: Set x = 0 \[y=1\] \[x\text{-intercept}\]: Set y = 0 \[x=-\frac{1}{2}\] The line passes through \[\left( 0,1 \right)\] and \[\left( -\frac{1}{2},0 \right)\] Now, consider the second equation \[x+y=-5\] \[y\text{-intercept}\]: Set x = 0 \[y=-5\] \[x\text{-intercept}\]: Set y = 0 \[x=-5\] The line passes through \[\left( 0,-5 \right)\] and \[\left( -5,0 \right)\] So, the intersection of both equations can be obtained by graphing them in the same plane as shown below: So, Coordinates of the intersection point is \[\left( -2,-3 \right)\] Now, check this point in both the equations, Put \[\left( -2,-3 \right)\]in \[2x-y=-1\], \[\begin{align} & 2\left( -2 \right)-\left( -3 \right)=-1 \\ & -4+3=-1 \\ & -1=-1 \end{align}\] Which is true. Now, Put \[\left( -2,-3 \right)\]in \[x+y=-5\], \[\begin{align} & -2-3=-5 \\ & -5=-5 \end{align}\] Which is true. Hence, both the equations are verified. Hence, solution of the system 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.