What does a negative minus a negative equal?

Question

-12 - -288 = 

 

Answer 1

Positive:

 

    -12 - ( -288) = -12 + 288 = 276

 

    Dealing with Sign numbers in Algebra

 

   Consider  Subtraction as switch, that when operates on a quantity changes the sign of that quantity:

 

      1 2  - ( + 10 ) = 12 - 10 =2

 

       12 - ( -10 ) = 12 + 10 = 22

 

        Therefore Subtraction of Positive numbers is subtraction.

                        Subtraction of Negative number is addition.

              

 

    

 

   

Answer 2

When you have a negative minus double negative, the double negative becomes positive.

 

So  - 12 + 288 = 276

Answer 3

Think of the number line.  If you're starting with a negative number, you're to the left of the 0.  If positive, you're on the right.

 

When you subtract a positive or add a negative, you have to move to the left.

Both of these are opposites together (subtract (neg) with positive and add with negative)

 

When you add a positive or subtract a negative, you have to move to the right.

Both of these are doubles.  (add (pos) with positive and subtract (neg) with negative)

 

You can't predict what sign the answer will be in any neg - neg problem, because it depends on where you're starting combined with how far you're moving left or right.  In your example, you start 12 left of 0 (or at -12) and take away a bunch of negative which is the same as adding positive (like in your mental health!).  So, this answer will be a positive.

 

I hope that helps.