A tangent to a circle at point P is a straight line that touches the circle at P. The tangent is perpendicular to the radius which joins the centre of the circle to the point P. As the tangent is a ...

The internet is stuffed with online quizzes and surveys, ranging from which "Friends" character you are to who you're about to vote for. But the BBC recently asked something more profound of its ...

As the tangent is a straight line, the equation of the tangent will be of the form \(y = mx + c\). We can use perpendicular gradients to find the value of \(m\), then use the coordinates of P to find ...