The line y=mx−2y = mx - 2y=mx−2 is a tangent to the circle x2+kx+y2−8y+5=0x^2 + kx + y^2 - 8y + 5 = 0x2+kx+y2−8y+5=0.
Find the two possible values of m m\,m in terms of kkk, giving your answers in exact form.
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.