Higher Plus

A histogram has two bars: one 20 units wide with frequency density 1.2, one 5 units wide with density 0.6. How many values in total?

Simplify 20 + 245, giving your answer in the form a b.Simplify sqrt(20) + sqrt(245), giving your answer in the form a sqrt(b).

Solve x² + y² = 289 and y = x + 7 simultaneously.Solve x^2 + y^2 = 289 and y = x + 7 simultaneously.

y is directly proportional to x². When x = 3, y = 63. Work out the positive value of x when y = 343.y is directly proportional to x^2. When x = 3, y = 63. Work out the positive value of x when y = 343.

The point (5, 12) lies on the circle x² + y² = 169. Work out the gradient of the tangent to the circle at that point.The point (5, 12) lies on the circle x^2 + y^2 = 169. Work out the gradient of the tangent to the circle at that point.