Answer:
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Explanation:
While it may look like the associative property was correctly demonstrated, it was not. Generally, this property says that for
we have:
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Let
,
and
. We then have:
![(7-x)-5 = [7+(-x)]+(-5) = (a+b)+c.](https://img.qammunity.org/2020/formulas/mathematics/middle-school/unzfwyii59g3bea195dco7s5s10gv9juus.png)
Applying the associative property, we get:
![(a+b)+c = a+(b+c) = 7 + [-x + (-5)] = 7 - x - 5 = 7-(x+5).](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hkpxon8vrrsxxxe0u9u2hivn7xns4u2zsg.png)
We now notice that the sign inside the parenthesis is wrong, so the answer is:
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