Precalculus (6th Edition) Blitzer

Published by Pearson
ISBN 10: 0-13446-914-3
ISBN 13: 978-0-13446-914-0

Chapter 2 - Section 2.7 - Polynomial and Rational Inequalities - Exercise Set - Page 413: 19

Answer

$(-\infty, 0]\cup [4,\infty)$; see graph.

Work Step by Step

Step 1. Rewrite the inequality as $x^2-4x\geq0$ or $x(x-4)\geq0$; the boundary points are $x=0,4$ Step 2. Using test points to examine signs across the boundary points, we have $...(+)..(0)...(-)...(4)...(+)...$; thus the solutions are $x\leq0$ plus $x\geq4$ Step 3. We can express the solutions on a real number line as shown in the figure. Step 4. We can express the solutions in interval notation as $(-\infty, 0]\cup [4,\infty)$
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.