If a pupil is given a formula they may be asked to substitute values into a formula.

e.g. Find the value of 4a + 2 when a = 2 (Remember 4a means 4 multiplied by the value of a)

In order to substitute into a formula correctly you must be aware of order of operations. ( see section on order of operations)

Notice how the power has been worked out first, then the multiplication and finally the addition.