SOLUTION: 9) A student claims that a – b – c is the same as a – ( b – c ). How do you respond?

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Question 176323: 9) A student claims that a – b – c is the same as a – ( b – c ). How do you respond?
Found 2 solutions by jim_thompson5910, solver91311:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let's assume that a-b-c=a-%28b-c%29


a-b-c=a-%28b-c%29 Start with the given equation.


a-b-c=a-b%2Bc Distribute the negative. Remember, this negative applies to EVERYTHING in the parenthesis. So change the sign of "b" to get "-b" and change the sign of "-c" to get "c"

-b-c=-b%2Bc Subtract "a" from both sides.


-c=c Subtract "b" from both sides.


Because the equation above is NOT true for all values of "c" (in fact, it's only true if c=0), this means that a-b-c=a-%28b-c%29 is NOT true.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
I would respond WRONG!!! (But I would say it nicely. No point in hurting anyone's feelings.)

a+-+%28b+-+c%29+=+a+%2B+%28-1%29%28b+-+c%29+=+a+-+b+%2B+c+%3C%3E+a+-+b+-+c