Elementary Geometry for College Students (5th Edition)

Published by Brooks Cole
ISBN 10: 1439047901
ISBN 13: 978-1-43904-790-3

Chapter 11 - Section 11.4 - Applications with Acute Triangles - Exercises - Page 528: 28

Answer

$28.6^{\circ} $

Work Step by Step

We use the Law of Cosines to find: $cos(2\alpha)= \frac{-(6^2) + 5^2 + 7^2 }{2(5)(7)} \\ cos2\alpha = .54 \\ \alpha = 28.6^{\circ} $
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.