9 times 75 is 675, but what is the answer if both 9 and 75 are negative numbers? Here we will determine if the answer to negative 9 times negative 75 is positive 675 or negative 675.
There are many different ways to explain and determine if the answer to negative 9 times negative 75 is -675 or +675 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 -675 is the correct answer using basic algebra.
We will test if -675 is correct by setting up the equation negative 9 times negative 75 equals negative 675, and then simplifying the equation to see if it is true.
(-9) (-75) = (-675)
Divide both sides of the equation by (-75) :
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| = |
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The numerator and denominator on the left side both have (-75) which even each other out and can be removed:
| (-9) = |
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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:
| (-9) = |
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A numerator of 675 and denominator of 75 on the right side is the same as 675 divided by 75 which is 9. Now we end up with this untrue equation:
(-9) = (9)
-9 is NOT equal to 9, thus we have proven that negative 9 times negative 75 is not equal to -675. The answer must therefore be 675:
-9 x -75 = 675
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 9 times negative 75 will always have a positive answer.
Negative Times Negative Calculator
Here you can multiply another two negative numbers together.
What is negative 9 times negative 76?
Here is the next problem on our list that we have explained and calculated.
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