Question 773270
radius = r
d= distance of chord from center

length of chord = c

half the length of chord ,the radius and the distance from center form a right triangle

(c/2)^2= r^2-d^2

c^2/4 = (r^2-d^2)

c^2=4(r^2-d^2)

{{{c= 2*sqrt(r^2-d^2)}}}