Question 332014
Hello, 
I'll help you on the first one--let's see if you can figure out the others.
28+x=7-2x
First subtract x from both sides to get:
28=7-3x
Now subtract 7 from both sides to get:
21=-3x
Now divide -3 into both sides to result in:
x=-7 
We can check to see if this is correct by plugging the answer in. 
(Hint: What we try to do in these equations is get the variable, in this case "x" all by itself.
Make sense?
RJ
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