Question

Can someone please help me? I think there's something wrong with this exercice (or else I'm doing it wrong).

Thanks!

Answer 1

The answers to your question are: 7x + 3 goes with the other 7x + 3, 7x + 3x = 10x, 7x - 3x = 4x, 7x * 3 = 21x, 5x + 5x = 25x, 7x * 3x = 21x². Hope this helped. :/

Answer 2

Note that when adding or subtracting, you can only combine like terms. However, when multiplying and dividing, you can combine un-like terms, as long as they follow the rules.


These terms cannot be combined because they do not have the same variables, and you are adding.
7x + 3 = 7x + 3

These terms can be combined, because they have the same number of variables, "x".
7x + 3x = 10x

These terms can also be combined because they have the same amount of variables
7x - 3x = 4x

These terms can be combined because you are multiplying
7x(3) = 21x

These terms can be combined because they have the same amount of variables.
5x + 5x = 10x

These terms can be combined because you are multiplying. Note that when you multiply one x with another x, you get x²
7x(3x) = 21x²


hope this helps