# Pre-Algebra for 5-6th graders PART 1: Evaluating Addition and Subtraction variables

47 views

If you're need homework help with this or you want to be ahead of your game, this tutorial is just for you!

Let's say we have this expression to solve:
5+x=10
The goal is to get the variable itself. So how do we do that?
We do the inverse operation, or the opposite operation. So what's the inverse operation of addition? Subtraction right? So, we solve 5-5, which is zero, so the number 5 in the problem will instantly eliminate itself.
5-5=0 +x=10
But what we do to one side, we must do to the other. So 10-5 is 5. Therefore, the variable x is equal to 5.
x=10-5=5
x=5

2. Subtraction

Let's say we have this expression to solve:
x-10=50
As we said in the addition process, our goal is to get the variable itself by doing the inverse operation. What's the inverse operation of subtraction? Addition, right? So, as we add 10+10, it instantly eliminates itself.
x- 10+10=50
But what we do to one side, we must do to the other, so 50+10 is 60. Therefore, the variable x is equal to 60.
x=50+10=60

IMPORTANT NOTES:
Goal: Get the variable itself
Any other way you solve this, 50% chance you might get it wrong
The letter of the variable does not matter. Here, I just used x. You do not have to use x for every equation. But keep in mind, when you're making an expression for a word problem, make sure the variable is related to the problem.

For more information, I suggest going on tutorial sites, such as Khan's Tutorial:
Regular Pre-Algebra-

If you have any questions or comments, ask me, 2CutePandiLou. Hope this helps!!
Part 2 is coming soon! (Evaluating variables Multiplication and Division)