Daily Practice - Higher Plus

A histogram has two bars: one 20 units wide with frequency density 2.5, one 20 units wide with density 3.5. How many values in total?

Simplify √72 + √32, giving your answer in the form a √b.Simplify sqrt(72) + sqrt(32), giving your answer in the form a sqrt(b).

Make x the subject of 3x + 3 = y(x + 3).

y is directly proportional to x². When x = 5, y = 75. Work out the positive value of x when y = 108.y is directly proportional to x^2. When x = 5, y = 75. Work out the positive value of x when y = 108.

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.