center C has a radius of 13.Chord AB=10.find the distance from the center of the circle to chord AB. CD=?

Answer 1

make a sketch, join the centre to A, and complete the right-angled triangle.
let the distance from the centre to the chord be x
x^2 + 5^2 = 13^2
x^2 = 169-25 = 144
x = √144 = 12

Where does CD enter the picture?
Where is D ?
Your opening sentence of "center C has a radius of 13" makes no sense.