Higher Plus

The point (9, 40) lies on the circle x² + y² = 1681. Work out the gradient of the tangent to the circle at that point.The point (9, 40) lies on the circle x^2 + y^2 = 1681. Work out the gradient of the tangent to the circle at that point.

A bag holds 4 red, 7 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 5 units wide with frequency density 2, one 20 units wide with density 0.6. How many values in total?

Rationalise the denominator of 30/3, giving your answer in its simplest form.Rationalise the denominator of 30/sqrt(3), giving your answer in its simplest form.

Solve x² + y² = 25 and y = x + 1 simultaneously.Solve x^2 + y^2 = 25 and y = x + 1 simultaneously.