7 times 99 is 693, but what is the answer if both 7 and 99 are negative numbers? Here we will determine if the answer to negative 7 times negative 99 is positive 693 or negative 693.
There are many different ways to explain and determine if the answer to negative 7 times negative 99 is -693 or +693 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 -693 is the correct answer using basic algebra.
We will test if -693 is correct by setting up the equation negative 7 times negative 99 equals negative 693, and then simplifying the equation to see if it is true.
(-7) (-99) = (-693)
Divide both sides of the equation by (-99) :
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| = |
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The numerator and denominator on the left side both have (-99) which even each other out and can be removed:
| (-7) = |
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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:
| (-7) = |
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A numerator of 693 and denominator of 99 on the right side is the same as 693 divided by 99 which is 7. Now we end up with this untrue equation:
(-7) = (7)
-7 is NOT equal to 7, thus we have proven that negative 7 times negative 99 is not equal to -693. The answer must therefore be 693:
-7 x -99 = 693
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 7 times negative 99 will always have a positive answer.
Negative Times Negative Calculator
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