
72 times 28 is 2016, but what is the answer if both 72 and 28 are negative numbers? Here we will determine if the answer to negative 72 times negative 28 is positive 2016 or negative 2016.
There are many different ways to explain and determine if the answer to negative 72 times negative 28 is -2016 or +2016 using mathematical terms such as additive inverse and mathematical laws like the Distribute Law.
We will take a different approach - process of elimination: We will simply test if -2016 is the correct answer using basic algebra.
We will test if -2016 is correct by setting up the equation negative 72 times negative 28 equals negative 2016, and then simplifying the equation to see if it is true.
(-72) (-28) = (-2016)
Divide both sides of the equation by (-28) :
| = |
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The numerator and denominator on the left side both have (-28) which even each other out and can be removed:
(-72) = |
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The numerator and denominator on the right side both have a minus sign (-) which even each other out and can be removed:
(-72) = |
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A numerator of 2016 and denominator of 28 on the right side is the same as 2016 divided by 28 which is 72. Now we end up with this untrue equation:
(-72) = (72)
-72 is NOT equal to 72, thus we have proven that negative 72 times negative 28 is not equal to -2016. The answer must therefore be 2016:
-72 x -28 = 2016
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 72 times negative 28 will always have a positive answer.
Negative Times Negative Calculator
Here you can multiply another two negative numbers together.
What is negative 72 times negative 29?
Here is the next problem on our list that we have explained and calculated.
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