Problem: The length of the common chord of two intersecting circles is 16 feet. If the radii are 10 feet and 17 feet, the distance between the centers of the circles, expressed in feet, is:
Answer Choices:
A. 27
B. 21
C. 389​
D. 15
E. undetermined
Solution:
From the diagram we have OP2=OA2−AP2=102−82,OP=6
