Elementary Geometry for College Students (6th Edition)

Published by Brooks Cole
ISBN 10: 9781285195698
ISBN 13: 978-1-28519-569-8

Chapter 1 - Section 1.4 - Angles and Their Relationships - Exercises - Page 37: 45

Answer

$\angle ABC=135^{\circ}$

Work Step by Step

Since vertex $b$ measures $360^{\circ}$ and the smaller reflex angle of $\angle DBC $ measures $90^{\circ}$, the larger reflex angle of $\angle DBC$ equals $360^{\circ}-90^{\circ}=270^{\circ}$. This is bisected, meaning the resulting pieces are half that of the original. We want to find the angle measurement of one of these halves. $\frac{270}{2}^{\circ}=135^{\circ}$.
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.