Question

A chord 20 inches long is 4 inches from the center of a circle, as shown below. What is the radius of the circle, to the nearest tenth of an inch


A. 4.0

B. 10.7

C. 10.8

D. 11.0

E. 21.6

Answer 1

Answer:

  C. 10.8

Step-by-step explanation:

The shortest distance from a line to a point is along a path at right angles to the line. That is, the segment marked 4 is a perpendicular bisector of the segment marked 20. Together with the radius (r), it makes a right triangle with legs 4 and 10. The Pythagorean theorem tells us ...

  r² = 4² + 10²

  r = √(16 +100) ≈ 10.77033

The radius of the circle is about 10.8 inches.