SOLUTION: find the center and radius of a circle that has a diameter with endpoints (-4,-19) and (12, 11.

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Question 425281: find the center and radius of a circle that has a diameter with endpoints (-4,-19) and (12, 11.
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
The center is the midpoint of the endpoints, so the center is at (4, -4) (obtain this by taking the average of the x-coordinates, average of the y-coordinates). The radius of the circle is the distance from (4, -4) to, say, (12, 11). By the distance formula, this is equal to

r+=+sqrt%28%2812-4%29%5E2+%2B+%2811-%28-4%29%29%5E2%29+=+sqrt%288%5E2+%2B+15%5E2%29+=+17

So the radius is 17.