Answer: 
Step-by-step explanation:

Remove all those parentheses by multiplying. Note: 2 and 2 cancel out.

Subtract 2x

Combine like terms;

Divide by -3

Rewriting it;

The steps involving properties of equality are shown in painful detail.
For Step 4, you add 7 to both sides of the equation (with the goal of cancelling the -7 on the left). So you have
6x -7 +7 = 12 +7 . . . . . . . showing 7 added to both sides
In the next step, this is simplified to the way you might have written it to start with:
6x = 19
There should be no confusion in any of this. All solutions of all equations make use of the properties of equality like this. Addition is used to cancel subtraction, division is used to cancel multiplication. (Root-taking cancels powers, and vice-versa; inverse trig functions cancel trig functions; and so on.)
Answer:
I'm not sure what method this was but I added up all the numbers and divided it by 5.
Step-by-step explanation:
The answer is 13. I added up all the numbers to get 65. Then, I divided 65 by 5 to get 13. Hope this helped!
For starters, 700 and 600 are different
Answer:

Step-by-step explanation:
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