Multiplying and Dividing Terms

Multiplying and Dividing Terms

GCSE(F), GCSE(H),

Terms can be multiplied and divided, together with the coefficients (numbers). 3 x a can be written as 3a (the times sign is removed to stop it being confused with an x). And b x c is written as bc.

4b x 3e is the same as 4 x 3 x b x e = 12be.

The calculation b x c is the same as c x b, because order in a multiplication does not matter. Therefore bc = cb, although it is normal to put the letters in alphabetical order. Numbers should be placed at the front of a term.

The number 1 is not normally written at the front of a term: so 1x is written as x.

A number divided by itself is 1; similarly a ÷ a = 1. And 5x ÷ x = 5.

The rules for multiplying and diving with negative numbers still apply: -2x x -y = +2xy.

Examples

1. Simplify 5 x -a.

Answer: -5a

2. Simplify 3 x b x 4 x c.

Answer: 12bc

3 x 4 = 12; then the remaining letters are put together without the times sign.