SOLUTION: How can 12 - 6 = -6 This is a problem I got from my algebra teacher today. 12 - 6 = -n she said the answer is -6 How can that be true when in elementary school I learned that 1

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Question 222842: How can 12 - 6 = -6
This is a problem I got from my algebra teacher today.
12 - 6 = -n
she said the answer is -6
How can that be true when in elementary school I learned that 12 - 6 = 6.
Thanks
Found 3 solutions by jim_thompson5910, rapaljer, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
What she meant by "the answer is -6" is that the value of n=-6 satisfies the equation 12-6=-n. Take note that the left side is simply 6 (since 12-6=6). So the equation then becomes 6=-n. Now plug in n=-6 to get 6=-%28-6%29 and now simplify 6=6. Since this is a true equation, this verifies the answer.


Note: none of this means that 12-6=-6 (since this isn't even true anyway).

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
If the question had been 12-6=n, then the answer would have been n=6.

However the question was
12-6=-n
6=-n

Divide both sides by -1:
6%2F-1=%28-n%29%2F-1
-6=n
n=-6

Check:
12-6=-n
6=-(-6)
6=6 It checks!!

R^2

Dr. Robert J. Rapalje
Seminole State College of Florida
Altamonte Springs Campus

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How can 12 - 6 = -6
Ans: It isn't.
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This is a problem I got from my algebra teacher today.
12 - 6 = -n
she said the answer is -6
Ans: It is.
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Solving the equation:
12 - 6 = -n
Simplify the left side to get:
6 = -n
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Multiply both sides by -1 to get:
n = -6
That is what your teacher said.
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Cheers,
Stan H.