Precalculus: Concepts Through Functions, A Unit Circle Approach to Trigonometry (3rd Edition)

Published by Pearson
ISBN 10: 0-32193-104-1
ISBN 13: 978-0-32193-104-7

Chapter 7 - Applications of Trigonometric Functions - Section 7.3 The Law of Cosines - 7.3 Assess Your Understanding - Page 559: 36

Answer

$B \approx29.9^\circ$ $C\approx65.1^\circ$ $c \approx12.7$

Work Step by Step

1. Use the Law of Sines, we have $\frac{14}{sin85^\circ}=\frac{7}{sinB}=\frac{c}{sinC}$, thus $B=sin^{-1}(\frac{7sin85^\circ}{14})\approx29.9^\circ$ 2. Find the third angle $C\approx(180-85-29.9)=65.1^\circ$ 3. thus $c=\frac{14sin65.1^\circ}{sin85^\circ}\approx12.7$
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.