Precalculus (6th Edition) Blitzer

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

Chapter 9 - Section 9.3 - The Parabola - Exercise Set - Page 998: 75



Work Step by Step

Step 1. Using the given figure, set the vertex of the arch as the origin. We can write the general form of the equation for the parabola as $x^2=4py$ Step 2. As point $(100,-50)$ is on the curve, we have $100^2=4p(-50)$, which gives $p=-50$ Step 3. At 30 feet from the center, we have $x=30$. Thus $y=\frac{x^2}{4p}=\frac{30^2}{4(-50)}\approx-4.5$, which means that at $x=30$, the arch is $50-4.5=45.5\ ft$ from the water and the boat (30 feet high) is clear to pass.
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.