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Janet Brien

August 28, 2017 21:50

1

This is the math question:

 (-3)³ - 4²

The answer is -43 but I don't understand why it isn't -11.

Is it a mistake?

I would understand -43 being correct if it said: - -4²

but it doesn't. I would really love an explanation! Thank you in advance!

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4 comments

Pei-Hsin Lin 林培心 🌸

January 12, 2018 23:45

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If you think about it in terms of money, two debts put together make an even bigger debt.
```
(-3)³ - 4² =
-27 - 16 =
-27 + (-16) = 
-43
```
The answer would be 11 if the problem were slightly different.
```
(3)³ - 4² =
27 - 16 =
11
```
lynn sorsoli

August 29, 2017 18:03

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The first part of the above comment is an excellent explanation, but the second part has a typo. The answer is just 11 there, not -11.
Janet Brien

August 29, 2017 20:22
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Thank you very much for the explanation! I understand now. Also, I have been practicing these kinds of math problems and now that I look at this problem again, I see the correct answer, not the wrong one.

Thank you both for your input and explanations! :)
Pei-Hsin Lin 林培心 🌸

January 12, 2018 23:46

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Thanks for catching that, Lynn.

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