College Algebra (10th Edition)

Published by Pearson
ISBN 10: 0321979478
ISBN 13: 978-0-32197-947-6

Chapter 2 - Section 2.4 - Circles - 2.4 Assess Your Understanding - Page 186: 26

Answer

(a) The circle has a center (-1,1) and a radius of $\sqrt2$ units. (b) See below. (c) There are two x-intercepts: (-2,0) and (0,0). There are two y-intercepts: (0,0) and (0,2).

Work Step by Step

First, we need to make sure that the equation is in standard form $(x-h)^2+(y-k)^2=r^2$ In this case, we need to tidy the equation up a bit: $3(x+1)^2+3(y-1)^2=6$ $(3(x+1)^2+3(y-1)^2)/3=6/3$ $(x+1)^2+(y-1)^2=2$ $(x+1)^2+(y-1)^2=\sqrt2^2$ Now we can find the center (h,k) and the radius. The x-intercepts are all points of a graph when y=0: $(x+1)^2+(0-1)^2=2$ $(x+1)^2+1=2$ $(x+1)^2=1$ $\sqrt{(x+1)^2}=\sqrt1$ There are two x-intercepts: $x_1+1=-1$ $x_1=-2$ $x_2+1=1$ $x_2=0$ The y-intercepts are all points of a graph when x=0: $(0+1)^2+(y-1)^2=2$ $1+(y-1)^2=2$ $(y-1)^2=1$ $\sqrt{(y-1)^2}=\sqrt{1}$ There are two y-intercepts: $y_1-1=-1$ $y_1=0$ $y_2-1=1$ $y_2=2$
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.