what is the radius of circle O

Answer:
8.5 units
Step-by-step explanation:
first we gotta find the length of the diameter. they made it into a triangle, so we can use pythagorean theorem.
15² + 8² = c²
225 + 64 = c²
289 = c²
17 = c
so now we know that the length of the diameter is 17 units, so the radius would be half of that.
17 ÷ 2 = 8.5
so the radius is 8.5