Thinking Mathematically (6th Edition)

Published by Pearson
ISBN 10: 0321867327
ISBN 13: 978-0-32186-732-2

Chapter 10 - Geometry - 10.3 Polygons, Perimeter, and Tessellations - Exercise Set 10.3 - Page 637: 44

Answer

The measure of each angle of a 5-sided polygon represented by x is\[108{}^\circ \].

Work Step by Step

Sum of the measures of the angles will be determined by using the formula\[\left( n-2 \right)\times 180\]. The sides of the polygon, n is 5. Compute the sum of the angles of a polygon with 5 sides as shown below: \[\begin{align} & \text{Sum of angles}=\left( n-2 \right)\times 180{}^\circ \\ & =\left( 5-2 \right)\times 180{}^\circ \\ & =3\times 180{}^\circ \\ & =540{}^\circ \end{align}\] A measure of an angle of an irregular polygon will be determined by adding all the interior angles and subtract from the sum of the measures of all 5 angles, which is\[{{540}^{o}}\]. \[\begin{align} & \text{Measure of each angle of a polygon}=108{}^\circ +6x-12{}^\circ +5x+8{}^\circ +4x+28{}^\circ +3x+48{}^\circ \\ & {{540}^{o}}={{180}^{o}}+18x \\ & x=\frac{540{}^\circ -180{}^\circ }{18} \\ & =\frac{360{}^\circ }{18} \end{align}\] \[=20{}^\circ \] Compute the other angles by substituting the values of x as mentioned below: First angle: \[\begin{align} & \text{Measure of angle}=6x-12{}^\circ \\ & =\left( 6\times 20{}^\circ \right)-12{}^\circ \\ & =108{}^\circ \end{align}\] Second angle: \[\begin{align} & \text{Measure of angle}=5x+8{}^\circ \\ & =\left( 5\times 20{}^\circ \right)+8{}^\circ \\ & =108{}^\circ \end{align}\] Third angle: \[\begin{align} & \text{Measure of angle}=4x+28{}^\circ \\ & =\left( 4\times 20{}^\circ \right)+28{}^\circ \\ & =108{}^\circ \end{align}\] Fourth angle: \[\begin{align} & \text{Measure of angle}=3x+48{}^\circ \\ & =\left( 3\times 20{}^\circ \right)+48{}^\circ \\ & =108{}^\circ \end{align}\]
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.