- Thread starter Keeyn
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It's not easy to follow what you are saying; your term "break down" is confusing, and you are using "solve" where you mean "evaluate".

I think you are saying that when you are evaluating the expression 3 - 8(5), you do the multiplication 8(5) = 40 first, and then evaluate 3 - 40 = -37. This is a matter of determining the meaning of the expression, following the traditional order of operations; sometimes there can be other ways you can carry out an evaluation, which are guaranteed to give the same result.

All you can do with the expression (2x + 5) + 2 is to simplify it. Here, the parentheses have no real effect (because we normally evaluate left to right anyway), so we can write it as 2x + 5 + 2; but more important, we can apply the associative property of addition to see that it is equivalent to 2x + (5 + 2) = 2x + 7.

If you were evaluating the expression for some given value of x, then you would, as you suggest, evaluate 2x + 5 first, then add 2. Or, you could use the facts I mentioned in the last paragraph, and just evaluate 2x + 7. You will get the same result either way.

Does that answer your question? If not, can you tell us what your goal is?

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If you're looking at the expression:… In a simple expression like (2x+5)+2, can we look at 2x+5 separately first which still gives 2x+5 or we need to see (2x+5)+2 as the bare minimum to give 2x+5+2?

(

and you're seeing

So, it's not necessary to view the given expression as 2x + 5 + 2, at the start. What's important here is the process of simplification -- and that concept has to do with "combining like-terms".

Therefore, after you see 2x+5 as one object, and then parse (break down?) that a second object is being added to the first, your next thought is to recognize that 5 and 2 are like-terms (i.e., they are both constants) -- different from 2x (which is a variable term). In other words, we simplify the given expression by combining the like-terms:

2x + 7

Also, be aware that there are often a number of ways to carry out steps that all arrive at the same result. So, a personal style eventually takes hold.

If you're thinking about something else (regarding break downs and bare minimums), please explain in more detail. Thanks

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When I asked what your goal was, I was asking what you are trying to do with the expression.

If you are told to evaluate it for some value of x, then you can do whatever you do in evaluating any expression, piece by piece. If x = 4, then 2x is 8; 2x + 5 is 13; and (2x + 5) + 2 is 15.

If you are told to simplify the expression, then you do what I suggested using the associative property. Are you familiar with that? Have you learned to simplify expressions yet?

The expression certainly

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What does "break open the bracket" mean? Is that something you've been taught, or your own terminology?

The reason you can rewrite (2x+5)+2 as 2x+5+2 is simply that they

In other cases, like 2(2x + 5) = 4x + 10, you can do it because there is a property (in this case, the distributive property) that tells you that doing this doesn't change the value of the expression.

The reason you

All you have to do is know what you