Higher Plus

The point (12, 16) lies on the circle x² + y² = 400. Work out the gradient of the tangent to the circle at that point.The point (12, 16) lies on the circle x^2 + y^2 = 400. Work out the gradient of the tangent to the circle at that point.

A bag holds 6 red, 4 blue and 6 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

A histogram has two bars: one 20 units wide with frequency density 1.2, one 25 units wide with density 0.8. How many values in total?

Rationalise the denominator of 24/2, giving your answer in its simplest form.Rationalise the denominator of 24/sqrt(2), giving your answer in its simplest form.

Solve x² + y² = 100 and y = x - 2 simultaneously.Solve x^2 + y^2 = 100 and y = x - 2 simultaneously.