69 times 40 is 2760, but what is the answer if both 69 and 40 are negative numbers? Here we will determine if the answer to negative 69 times negative 40 is positive 2760 or negative 2760.
There are many different ways to explain and determine if the answer to negative 69 times negative 40 is -2760 or +2760 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 -2760 is the correct answer using basic algebra.
We will test if -2760 is correct by setting up the equation negative 69 times negative 40 equals negative 2760, and then simplifying the equation to see if it is true.
(-69) (-40) = (-2760)
Divide both sides of the equation by (-40) :
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| = |
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The numerator and denominator on the left side both have (-40) which even each other out and can be removed:
| (-69) = |
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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:
| (-69) = |
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A numerator of 2760 and denominator of 40 on the right side is the same as 2760 divided by 40 which is 69. Now we end up with this untrue equation:
(-69) = (69)
-69 is NOT equal to 69, thus we have proven that negative 69 times negative 40 is not equal to -2760. The answer must therefore be 2760:
-69 x -40 = 2760
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 69 times negative 40 will always have a positive answer.
Negative Times Negative Calculator
Here you can multiply another two negative numbers together.
What is negative 69 times negative 41?
Here is the next problem on our list that we have explained and calculated.
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