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In order of operation, does combining like terms always come after reordering?

I understand that you work from left to right

I understand that first you solve what is inside ( ) then inside brackets and I understand that fractions are considered as symbols and they come first as well.  

I understand that X and / come before + and -.

Is it always after these rules have been followed to the max that you combine like terms?  

Is there a simple way to understand the order beyond the basics?


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2 Answers

What I got form your original statement is ‘when do I combine like terms’? For example, you have an expression: 4x + (3x +2) = 9. In this problem you can’t do anything inside the parenthesis so you can drop them, and combine like terms. The new expression would be 7x + 2 = 9…. And the answer would be 7x = 7, and x = 7. Some problems may be longer than others, and I like to combine as I go. I know this is a more simplistic answer than what James has provided but pay attention to what is inside those Parenthesis first. Have a good one.

The rules are as follows:

If you can remember this phrase, you should be good.

Please Excuse My Dear Aunt Sally

P = Parenthesis E = Exponents M = Multiplication D = Division A = Addition S = Subtraction

Once you have done the first four, combining like terms comes with addition and subtraction.