1. The problem statement, all variables and given/known data A circle touches the line y=x at a pont P such that OP = 4*2^1/2 i.e 4root2 , where O is the origin.The circle contains the point (-10,2) in its interior and the length of its chord on the line x+y=0 is 6root2.Determine the equation of the circle. The attempt at a solution OK as its clear that the chord is perpendicular to the tangent so its part of the normal line and hence the diameter.So the length of the radius of the circle is 3root2. Secondly using under-root S1 = length of tangent drawn from (x1,y1) I got c= 32. I cant proceed any further.What use is the internal point?