SOLUTION:

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Question 408373:
Answer by cesardelrosario(3)   (Show Source): You can put this solution on YOUR website!
2x-4=x+9
solution:
2x-4=x+9
-9+2x-4=x+9-9
-13+2x=x
-13+2x-2x=x-2x
-13=-x
therefore, x=13