Question

How do you define a variable and write an expression for each phrase: the total of four times a number and twice the difference between the number and four?

Answer 1

first phrase: `4x`
seconds phrase: `2(x-4)`

Explanation:

Let us define the variable 'the number' as `x`.
`x` can be any number, which is why it is called a variable.

The first phrase, 'four times a number', is expressed as `4x`. Literally, `4*x`, or four times `x`.

The second phrase is harder, 'the difference between the number and 4' is simply our number subtract 4: `x-4`, but this is doubled, which becomes `2(x-4)`

Hope this helps!