SOLUTION: Suppose a chord in a circle is 80 centimeters long and it is 30 centimeters from the center of the circle. Find the measure of a radius of the circle.

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Question 79849: Suppose a chord in a circle is 80 centimeters long and it is 30 centimeters from the center of the circle. Find the measure of a radius of the circle.
Answer by zerosignal(28) About Me  (Show Source):
You can put this solution on YOUR website!
Break the geometry down into a right triangle, take half of the 80cm chord length (40cm), and use it as one leg of the triangle. Use 30cm for the other leg, and solve for the hypotenuse (which will be the radius).
you can use the Pythagorean Theorem to solve this: a%5E2%2Bb%5E2=c%5E2 and re-write to solve for "c" sqrt%28a%5E2%2Bb%5E2%29=c
Let a = 30
Let b = 40

sqrt%2830%5E2%2B40%5E2%29+=+c
sqrt%28900%2B1600%29+=+c
sqrt%282500%29+=+c
50+=+c
so the radius is 50 cm