Precalculus (6th Edition) Blitzer

Published by Pearson
ISBN 10: 0-13446-914-3
ISBN 13: 978-0-13446-914-0

Chapter 7 - Review Exercises - Page 877: 35


$(-3,-1)$, $(-3,1)$, $(3,-1)$, $(3,1)$

Work Step by Step

Re-arrange the given two equations and then use the addition method to get $8x^2+12y^2=84$ and $9x^2-12y^2=69$ $8x^2+12y^2+9x^2-12y^2=69+84$ This gives: $x^2=9 \implies x=3,-3$ when $x=3$ then we have $(2)(9)+3y^2=21 \implies y^2=1$ This gives: $y=1,-1$ Hence, our answers are: $(-3,-1)$, $(-3,1)$, $(3,-1)$, $(3,1)$
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.