A circle C C\,C with centre (2,1)(2, 1)(2,1) passes through the point (−1,k)(-1, k)(−1,k). A line L L\,L passes through the points (1,−4)(1, -4)(1,−4) and (10,2)(10, 2)(10,2).
Given that L L\,L is a tangent to CCC, find the possible values of kkk.
292 exam-style questions on Edexcel A Level Maths Circles, covering 6.1 Midpoints and Perpendicular Bisectors, 6.2 Equation of a Circle, 6.3 Intersections of Straight Lines and Circles, 6.4 Use Tangent and Chord Properties, and 6.5 Circles and Triangles. Each one has a worked solution and a mark scheme showing where the marks go.