Instead of using English words, we write algebra using mathematical notation:

- means, “the sum of
*x*and 2″, or alternatively, “*x*increased by 2″. Both refer to the same formula. - means “the difference between
*x*and 2″, or alternatively, “*x*decreased by 2″. Both refer to the same formula. - means “the product of 2 and
*x*“

A term is a combination of numbers and variables, involving only multiplication or division (and NOT addition or subtraction).

Examples of terms may be 2*x*, 3*xy*, 5*x*/*y*. As is evident, no plus or minus sign is present!

By convention, we write:

- Numbers before the variables. This is why we write 2
*x*, and not*x*2 - Variables in alphabetical order. This is why we write
*xyz*and not*yzx* *x*instead of 1*x*. You can leave out the 1

When we use variables, the variables can take on any value. For example, when we write “2*xy*“, the *x* and *y* can refer to -10, -9.999, 5, 20, etc… absolutely any value! However, if you’ve been given more information, such as that *x* is 2 and *y* is 3, you can determine its single value, by substituting, i.e. . This process of replacing a variable with a number is known as substitution.

Word questions make algebra more difficult. For example, if I consistently see Mandy 5 times a month, how many times will I see her in *x* months? Well, that would be 5*x*

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