SOLUTION: W/2 + 7 = 21 I subtracted 7 from both sides and got W/2 = 14 Then I multiplied both sides by 2 and I got W = 28 I know this is correct. My question is... My friend

Question 441049: W/2 + 7 = 21
I subtracted 7 from both sides and got
W/2 = 14
Then I multiplied both sides by 2 and I got
W = 28
I know this is correct. My question is... My friend did the problem this way... And I cannot figure out why is comes up with a different answer when all she did was start at a different place than I did. Can you explain why starting with multiplying by 2 does work?
W/2 +7=21
multiply both sides by 2
W + 7 = 42
subtract 7 from both sides
w = 35
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Your friend didn't multiply the 7 by 2.
-------
W/2 +7=21
multiply both sides by 2
W + 14 = 42
W = 28

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