71 times 87 is 6177, but what is the answer if both 71 and 87 are negative numbers? Here we will determine if the answer to negative 71 times negative 87 is positive 6177 or negative 6177.
There are many different ways to explain and determine if the answer to negative 71 times negative 87 is -6177 or +6177 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 -6177 is the correct answer using basic algebra.
We will test if -6177 is correct by setting up the equation negative 71 times negative 87 equals negative 6177, and then simplifying the equation to see if it is true.
(-71) (-87) = (-6177)
Divide both sides of the equation by (-87) :
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| = |
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The numerator and denominator on the left side both have (-87) which even each other out and can be removed:
| (-71) = |
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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:
| (-71) = |
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A numerator of 6177 and denominator of 87 on the right side is the same as 6177 divided by 87 which is 71. Now we end up with this untrue equation:
(-71) = (71)
-71 is NOT equal to 71, thus we have proven that negative 71 times negative 87 is not equal to -6177. The answer must therefore be 6177:
-71 x -87 = 6177
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 71 times negative 87 will always have a positive answer.
Negative Times Negative Calculator
Here you can multiply another two negative numbers together.
What is negative 71 times negative 88?
Here is the next problem on our list that we have explained and calculated.
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