Writing expressions with variables

Question

Four more than the product of three and a number

Answer 1

To get 4 more of something, you add. The product is the result of multiplication. We can call our number anything we want. Most people would use x. I like to use the first letter of what I'm dealing with, so I'll call it n. Three times n is simply written as 3n, just like 3 times you would be 3 Janelles.

Four more than the product of three and a number is...

3n + 4

Note, this is NOT 7. We do not add multiples of a variable to a constant, nor do we add multiples of different variables. 3n + 4 stays just as is until we assign a value to n.

For example, if n = 5...

3(5) + 4 = 15 + 4 = 19

If n = 8...

3(8) + 4 = 24 + 4 = 28

and so on.

Answer 2

Product indicates multiplication, so that part of the expression will be 3 times a number (here we will call that number x). Then to complete the expression, we will want to add 4 to the expression to get the following:

3x + 4