SOLUTION: Todd has drawn a cul-de-sac for a residential development plan. He used a compass to draw the cul-de-sac so that it would be circular. On his blueprint, the center of the cul-de-sa

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Question 865028: Todd has drawn a cul-de-sac for a residential development plan. He used a compass to draw the cul-de-sac so that it would be circular. On his blueprint, the center of the cul-de-sac has coordinates (-1, -1) and a point on the circle is (2, 3). What is the radius of the cul-de-sac?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use the distance formula, the distance between the two points is equal to the radius.
R%5E2=%28x%5B2%5D-x%5B1%5D%29%5E2%2B%28y%5B2%5D-y%5B1%5D%29%5E2
R%5E2=%282-%28-1%29%29%5E2%2B%283-%28-1%29%29%5E2
R%5E2=3%5E2%2B4%5E2
R%5E2=9%2B16
R%5E2=25
R=5