1 times 13 is 13, but what is the answer if both 1 and 13 are negative numbers? Here we will determine if the answer to negative 1 times negative 13 is positive 13 or negative 13.
There are many different ways to explain and determine if the answer to negative 1 times negative 13 is -13 or +13 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 -13 is the correct answer using basic algebra.
We will test if -13 is correct by setting up the equation negative 1 times negative 13 equals negative 13, and then simplifying the equation to see if it is true.
(-1) (-13) = (-13)
Divide both sides of the equation by (-13) :
|
| = |
|
The numerator and denominator on the left side both have (-13) which even each other out and can be removed:
| (-1) = |
|
The numerator and denominator on the right side both have a minus sign (-) which even each other out and can be removed:
| (-1) = |
|
A numerator of 13 and denominator of 13 on the right side is the same as 13 divided by 13 which is 1. Now we end up with this untrue equation:
(-1) = (1)
-1 is NOT equal to 1, thus we have proven that negative 1 times negative 13 is not equal to -13. The answer must therefore be 13:
-1 x -13 = 13
The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 1 times negative 13 will always have a positive answer.
Negative Times Negative Calculator
Here you can multiply another two negative numbers together.
What is negative 1 times negative 14?
Here is the next problem on our list that we have explained and calculated.
Copyright | Privacy Policy | Disclaimer | Contact