Question 148411
This forms a right triangle with a hypotenuse of 15 (the radius) and one side of 12. The other side is 1/2 of the chord.
{{{(C/2)^2 = 15^2 - 12^2}}}
C/2 = {{{sqrt(225 - 144)}}}
C/2 = {{{sqrt(81)}}}
C/2 = 9
Chord = 18