Suppose a chord is 20 inches long and is 24 inches from the center of the circle. How do you find the length of the radius?

1 Answer
Mar 10, 2016

r = 26"r=26

Explanation:

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A line segment from the 20" chord to the center of the circle is a perpendicular bisector of the chord creating a right triangle with legs of 10" and 24" with radius of the circle forming the hypotenuse.

We can use the Pythagorean theorem to solve for the radius.

a^2 + b^2 = c^2a2+b2=c2

a = 10"
b = 24"
c = ?"

10^2 + 24^2 = r^2102+242=r2
100 + 576 = r^2100+576=r2
676 = r^2676=r2
sqrt676 = r676=r
26" = r26=r