Question #N487
A circle has a radius of 5. A chord of the circle is 8 units long. What is the distance, in units, from the center of the circle to the chord?
A. 1
B. 3
C. 4
D. 5
Correct Answer is: B
A chord of a circle is a line segment whose endpoints lie on the circle. The distance from the center of the circle to a chord is the length of the perpendicular segment from the center to the chord. This perpendicular segment bisects the chord. Thus, we have a right triangle with legs of length 4 and a hypotenuse of length 5. Using the Pythagorean Theorem, we can find the length of the third side: 4^2 + x^2 = 5^2. Solving for x, we get x = 3.