Terms can be multiplied and divided, together with their coefficients (the numbers at the front of a letter).
`4b xx 3e` is the same as `4 xx 3 xx b xx e = 12be`.
The calculation `b xx c` is the same as `c xx b` (order in a multiplication does not matter). Therefore `bc = cb`, although it is normal to put the letters in alphabetical order.
When dividing a term by a number, consider only the number parts. For `12x ÷ 3`, divide 12 by 3 giving 4 and leave the `x` as it is to give an answer of `4x`.
A number divided by itself is 1; similarly `a ÷ a = 1`. And `5x ÷ x = 5`.
If one term is being divided by another term where both have the same variable, then calculate the number parts and the letter parts separately. `frac(15x)(3x) = frac(15)(3) \times frac(x)(x) = 5 \times 1 = 5`.
The rules for multiplying and diving with negative numbers still apply: `-2x times -y = +2xy`.
Simplify `5 xx -a`.
The `a` is negative: as it is a positive times a negative, the answer is negative.
Answer: ` -5a`
Simplify `3 xx b xx 4 xx c`
3 x 4 = 12; then the remaining letters are put together without the times sign.
Answer: `12bc`