SOLUTION: how to find the radius of a circle with a known chord length.

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Question 766071: how to find the radius of a circle with a known chord length.
Answer by reviewermath(1029) About Me  (Show Source):
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Q:
how to find the radius of a circle with a known chord length.
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A:
Given the length of the chord, the length of the radius depends on the distance of the chord from the center of the circle.
Example: The length of the chord is 8 cm and its distance from the center of the circle is 3 cm, then we use Pythagorean Theorem to find the length of the radius.

x is half the length of the chord.
Using Pythagorean Theorem:
x%5E2+%2B+y%5E2+=+r%5E2
r+=+sqrt%28x%5E2+%2B+y%5E2%29+
r+=+sqrt%284%5E2+%2B+3%5E2%29+=+sqrt%2825%29+=+5+
The length of the radius is 5 cm.