SpawnPoint - Where Game Begins

Pretty easy, actually.

In the first one (I'm going to assume you typed it correctly - a polyminal expression of a higher degree would have made it slighty more complicated and require the use of factoring), you want to isolate x. You wrote: 8x - 2 - 5x = 8, let's begin.

First, combine like terms. On the one side, 8x and -5x are like terms - they are multiples of x raised to the same exponent (1). Also on that side is a -2, "move" that to the other side by adding 2 to each side (effectively removing it from one side and placing it on the other). So, from the original, you are left with (without combining the 8x and the 5x) 8x - 5x (or 8x + -5x) and, on the other side, 8 + 2. Combine to get 3x = 10. From there, you're looking for one x, not three, so divide each side by three to get x = 10/3.

Moving on to the second problem: you wanted to know how to add polynomials. It's the same process: collect and add like terms. So, for adding -3x^2 - 5x + 1 and 8x^2 + 2x - 9, you want to first write an expression for the addition: -3x^2 - 5x + 1 + (8x^2 + 2x - 9) (notice the brackets, if it's subtraction this is very important as you have to distribute the negative one through the expression before you subtract it). From there, it becomes -3x^2 + 8x^2 - 5x + 2x + 1 - 9 (I just moved the terms that are similar beside each other to make addition easier...) -3x^2 + 8x^2 = 5x^2, -5x + 2x = -3x, and 1 - 9 = -8, so putting it all together, 5x^2 - 3x - 8.

Any questions?

Edit: math fail.

Ok, I can try. Let's start with the original expression again (expression is a mathematical sentence containing a set of operations, you know, like addition and subtraction and whatnot): 8x - 2 - 5x = 8. In solving for x, you're looking for a value of x that makes the expression true; that is, the left side and right side are equal. Currently, on the left side, you have multiples of x and a constant (this constant is a non-issue and is easy to deal with): you have eight x's in one term and negative five x's in the other (the term takes on the sign of the operation right before it - ... that's about as simple as I can make that, sorry). Since both of these are multiples of some number (x), you can add them together: 8x + -5x (you do addition, but it's really subtraction because you're adding a negative). Just ignore the x for a moment, it's not really an issue; adding is straight forward: 8 - 5 is what you're doing in simplest form (you can factor out the x, and this is what you're left with, by the way, but it doesn't appear that you have to know that). So, 8 - 5 = 3, but you took out the x, so just put it back in (this isn't _really_ how you do it, but I'm trying to make it simple for you...); 3x is what you're left with from that operation. You still have the two on that side, though. 3x - 2 = 8. Whatever operation is currently being done to the two, do the opposite to both sides (so, in this case you'd add two to each side) leaving you with 3x = 10. Again, you need only one x, not three, so divide each side by three giving you a final answer of x = 10/3.

I have to go, but if that doesn't help you with the second one, I'll come back later and work it out for you. I also took the time to do it on paper, as you'd see it done in an exam, to see if that could help clear things up for you.

It's kinda coming back to me a bit, It kinda helped out when you said "you do to one, you do to the other". Brought me back to like 8th grade when my math teacher was teaching us fractions, (yes laugh it up, I didn't learn factions til around that time). Kinda gave me a jolt.