Question 712631
Hint:


If you want to find the distance from line segment AB to the center, find the value of x


<img src="http://i150.photobucket.com/albums/s91/jim_thompson5910/Algebra%20dot%20com/2-9-201311-59-41PM_zpsc00b01d3.png">


Since you have a right triangle, you can use the Pythagorean theorem to set up the following equation {{{x^2+15^2 = 17^2}}}