Algebra and Trigonometry 10th Edition

Published by Cengage Learning
ISBN 10: 9781337271172
ISBN 13: 978-1-33727-117-2

Chapter 1 - 1.1 - Graphs of Equations - 1.1 Exercises - Page 79: 48

Answer

There is symmetry only about the x-axis. See graph. The intercepts: $(-5,0)$, $(0,-\sqrt5)$, $(0,\sqrt5)$.

Work Step by Step

$$x=y^2-5$$ Testing for the symmetry about the x-axis: $$x=(-y)^2-5$$ $$x=y^2-5$$ Since the resulting equation is the same as the original equation, there is symmetry about the x-axis. Testing for the symmetry about the y-axis: $$-x=y^2-5$$ $$x=-y^2+5$$ Since the resulting equation is not the same as the original equation, there is no symmetry about the y-axis. Testing for the symmetry about the origin: $$-x=(-y)^2-5$$ $$-x=y^2-5$$ $$x=-y^2+5$$ Since the resulting equation is not the same as the original equation, there is no symmetry about the origin. For $y=0$: $$x=0^2-5=-5$$ For $x=0$: $$0=y^2-5$$ $$y^2=5$$ $$y_1=-\sqrt5$$ $$y_2=\sqrt5$$ Thus, three points on the curve are at $(-5,0)$, $(0,-\sqrt5)$ and $(0,\sqrt5)$. Using the three points, the graph is as shown. The intercepts are as for x-intercept is $(-5,0)$, and for y-intercepts are $(0,-\sqrt5)$ and $(0,\sqrt5)$.
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.