What is negative 1 times negative 42? (-1 x -42)

What is negative 1 times negative 42?

1 times 42 is 42, but what is the answer if both 1 and 42 are negative numbers? Here we will determine if the answer to negative 1 times negative 42 is positive 42 or negative 42.

There are many different ways to explain and determine if the answer to negative 1 times negative 42 is -42 or +42 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 -42 is the correct answer using basic algebra.

We will test if -42 is correct by setting up the equation negative 1 times negative 42 equals negative 42, and then simplifying the equation to see if it is true.

(-1) (-42) = (-42)

Divide both sides of the equation by (-42) :

		(-1) (-42)
		(-42)

		(-42)
		(-42)

The numerator and denominator on the left side both have (-42) which even each other out and can be removed:

(-1) =

		(-42)
		(-42)

The numerator and denominator on the right side both have a minus sign (-) which even each other out and can be removed:

(-1) =

		(42)
		(42)

A numerator of 42 and denominator of 42 on the right side is the same as 42 divided by 42 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 42 is not equal to -42. The answer must therefore be 42:

-1 x -42 = 42

The above applies to all math problems where you multiply two negative numbers. Multiplying two negative numbers such as negative 1 times negative 42 will always have a positive answer.

Negative Times Negative Calculator
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What is negative 1 times negative 43?
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