Question

The equation (x-1)^2 + (y+1)^2 = r^2 represents circle J. The point D (0,3) lies on the circle. What is r, the length of the radius of circle J?

Answer 1

C. √17

Explanation:

The radius can be found by solving the given equation at the given point.

__

(x -1)^2 + (y+1)^2 = r^2 . . . . . . . given equation

(0 -1)^2 + (3 +1)^2 = r^2 . . . . . . using (x, y) = (0, 3)

1 +16 = r^2 . . . . . . . . . . . . simplify

r = √17 . . . . . . . take the square root