SOLUTION: A chord that is 15 cm long is 20 cm from the centre of a circle. Find the length of the radius??

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Question 290931: A chord that is 15 cm long is 20 cm from the centre of a circle. Find the length of the radius??
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A chord that is 15 cm long is 20 cm from the centre of a circle.
Find the length of the radius??
:
The 20 cm line bisects the chord, and you have a right triangle
r^2 = 7.5^2 + 20^2
r^2 = 56.25 + 400
r = sqrt%28456.25%29
r = 21.36 cm is the radius