Save guides, add subjects and pick up where you left off with your BBC account. Find the equation of a circle with radius 3 units and centre (0, 0). The radius, \(r = 3\) and \(r^2 = 9\), so the ...

Jean Kelly from Dublin's Institute of Education is here with six videos full of great advice and tips for the exam.

Find the equation of the tangent to the circle \(x^2 + y^2 = 25 \) at the point (3, -4). The tangent will have an equation in the form \(y = mx + c\) so to find the equation you need to find the ...