Question #N403
A circle has a radius of 5 units. 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. 2
B. 3
C. 4
D. 6
Correct Answer is: B
Draw a diagram of the circle with the chord and the radius drawn to the midpoint of the chord. The radius, the chord, and the line segment from the center of the circle to the midpoint of the chord form a right triangle, with the radius being the hypotenuse. Since the chord is 8 units long, the line segment from the center of the circle to the midpoint of the chord is 4 units long. The Pythagorean Theorem tells us that The distance from the center of the circle to the chord is 3 units.