Answer
$113$
Work Step by Step
FOIL the terms in the parentheses. Then combine like terms and make sure to convert $i^{2}$ into $-1$.
$(7+8i)(7-8i)$
$49-56i+56i-64i^{2}$
$49+64$
$113$
College Algebra (6th Edition)
by Blitzer, Robert F.
Published by
Pearson
ISBN 10:
0-32178-228-3
ISBN 13:
978-0-32178-228-1
Chapter 1 - Summary, Review, and Test - Review Exercises - Page 204: 52
Update this answer!
You can help us out by revising, improving and updating this answer.
Update this answerAfter 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.
