Basically, you’re trying to get to a statement that has y = where you only see the y by itself on one side of the equals sign.
You can think about the two sides of the equals sign as being separated by a net.
Imagine you have the left and right side and there is a y on the left side and some other things and there are some other things (but not y) on the right side. I’ll use squares, stars, triangles, and circles.
You would then want to remove things from the left side by subtracting. If you subtract something from itself, you’re left with zero of that thing.
In a more typical algebra equation, trying to solve for y
Again, you’re trying to isolate y =
So you can bring the terms with y either all to the left side or all to the right side. I brought them all to the left side. And I subtracted things from the left side that did not contain y. Since the two sides are equal (that’s what the equals sign means) then if you change the left side, you have to change the right side in the same way.
You can also use multiplication, division, and other things depending on what you start with.
Here, you have 2 y, and you want just y = , so you want to divide both sides by 2.