Some important points to revise from the chapter are: • An equation of the form ax + by + c = 0, where a, b and c are real numbers, such that a and b are not both zero, is called a linear equation in ...

A number machine is a way of writing rules using a flow diagram. The equation \(3j - 6 = 9\) can be shown on a number machine by writing out the functions that have been applied to \(j\) in the order ...

Melting and freezing are both physical changes, which are often easy to reverse. To reverse this process, the water would need to be cooled enough until it freezes back into ice. This works because ...