Daily Practice - Higher Plus

A histogram has two bars: one 20 units wide with frequency density 1.5, one 10 units wide with density 0.6. How many values in total?

Expand and simplify (6 + √5)(6 - √5).Expand and simplify (6 + sqrt(5))(6 - sqrt(5)).

In an algebraic proof, how would you write the next even number after 2n in terms of an integer n?

y is directly proportional to x². When x = 3, y = 72. Work out the positive value of x when y = 648.y is directly proportional to x^2. When x = 3, y = 72. Work out the positive value of x when y = 648.

In a circle theorem proof, a step uses the fact that two tangents are drawn to a circle from the same external point. State the reason being quoted.