The points A(4,a)A(4, a)A(4,a) and B(13,6)B(13, 6)B(13,6) lie on a circle. AB AB\,AB is a diameter of the circle and has a gradient of 13\displaystyle \frac{1}{3}31. The circle has equation (x−c)2+(y−d)2=e(x - c)^2 + (y - d)^2 = e(x−c)2+(y−d)2=e where ccc, d d\,d and e e\,e are rational numbers.
Find the values of aaa, ccc, d d\,d and eee.
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.