Higher Plus

The point (6, 8) lies on the circle x² + y² = 100. Work out the gradient of the tangent to the circle at that point.The point (6, 8) lies on the circle x^2 + y^2 = 100. Work out the gradient of the tangent to the circle at that point.

A bag holds 3 red, 6 blue and 3 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

On a histogram, a 4-wide bar and a 8-wide bar have the same frequency density of 2. How many more values are in the wider class?

A block has mass 780 g (to the nearest 10 g) and volume 14 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 780 g (to the nearest 10 g) and volume 14 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

Solve 12x² - 35x + 25 = 0.Solve 12x^2 - 35x + 25 = 0.