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?
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Answer:
C. √17
Step-by-step explanation:
The radius can be found by solving the given equation at the given point.
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(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