This means that, using Pythagoras’ theorem, the equation of a circle with radius r and centre (0, 0) is given by the formula \(x^2 + y^2 = r^2\). Find the equation of a circle with radius 3 ...

As the tangent is a straight line, the equation of the tangent ... in to the formula \(y = mx + c\) gives: Sketch a diagram to show the circle and the tangent at the point (2, 4) labelling this ...