Answer:
17 cm
Explanation:
In the above figure the question has been explained
the perpendicular from circle on the chord divides chord into two halves
let r be radius of circle in triangle NOY
NO= PO-PN = r-2 and YO=r(radius) YN=8cm
applying pythagorus theorem

after rearranging and solving the equation we get
r=17 cm
therefore the radius of the triangle is 17 cm
note: on observing we find that the sides of triangle are pythagorian triplet 17, 15 and 8