SOLUTION: how to solve this equation: 3a+7=a+9 ? Please help!

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Question 581741: how to solve this equation: 3a+7=a+9 ? Please help!
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+3a+%2B+7+=+a+%2B+9+
As long as you do the same thing to both sides,
the equation is still true
Subtract a from both sides
+3a+-+a+%2B+7+=+a+-+a+%2B+9+
+2a+%2B+7+=+9+
Now subtract 7 from both sides
+2a+%2B+7+-+7+=+9+-+7+
+2a+=+2+
Now divide both sides by 2
+%282%2F2%29%2Aa+=+%282%2F2%29+
+a+=+1+ answer
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check:
+3a+%2B+7+=+a+%2B+9+
+3%2A1+%2B+7+=+1+%2B+9+
+3+%2B+7+=+10+
+10+=+10+
OK