The circle C C\,C has equation x2+y2+8x−4y−14=0x^2 + y^2 + 8x - 4y - 14 = 0x2+y2+8x−4y−14=0
Complete both squares and use the result to give the centre and exact radius of CCC.
Show that the point (1,5)(1, 5)(1,5) lies on CCC.
143 exam-style questions on OCR A Level Maths 1.3 Coordinate Geometry in the x-y Plane, covering 1.3.1 Straight lines, 1.3.2 Parallel and perpendicular lines, 1.3.3 Straight line models, 1.3.4 Coordinate geometry of a circle, 1.3.5 Centre and radius by completing the square, 1.3.6 Circle properties, 1.3.7 Parametric equations of curves (A-level only), 1.3.8 Parametric equations in context (A-level only), and 1.3 Coordinate Geometry in the x-y Plane. Each one has a worked solution and a mark scheme showing where the marks go.