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 188: 57

Answer

The center is $(1,0)$

Work Step by Step

The line $x - 2y + 4 = 0$ is tangent to a circle at (0, 2). Slope of this tangent = $\frac{1}{2}$ So slope of radius from point (0,2) on the circle = -2 Equation of that radius line => $y - 2 = -2(x-0)$ => $\frac{y}{2}= -x + 1$ - - - (i) The line $y = 2x - 7$ is tangent to the same circle at (3, - 1). Slope of this tangent = $2$ So slope of radius from point (3, - 1) on the circle = $\frac{-1}{2}$ Equation of that radius line => $y - (-1) = \frac{-1}{2}(x-3)$ => $2y = -x + 1$ - - - (ii) Find the center of the circle Centre will be intersection of two radii lines Solving (i) and (ii) we get x = 1 and y = 0 So the center is $(1,0)$
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.