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When "subtracting" two negative numbers, how do you know which one to turn into a positive number hence that you can subtract? what if you had to subtract both numbers and order didnt matter such as in the algebra problem -2+x=-3+x. How do you subtract, or add like terms in such manner?

Question

QUICK HELP!

When "subtracting" two negative numbers, how do you know which one to turn into a positive number hence that you can subtract? what if you had to subtract both numbers and order didnt matter such as in the algebra problem -2+x=-3+x. How do you subtract, or add like terms in such manner?

anonymous · Answer

If you want to solve for x, that would be:

-2 + x = -3 + x
-2 + 2 + x = -3 + x + 2
0 + x = -1 + x 
x - x = -1
0 does not equal -1, therefore there exists no solution for this.

anonymous · Answer

Now to answer your question, suppose we have:
|dw:1342209383175:dw|

anonymous · Answer

yes.

anonymous · Answer

You turn the SECOND number into positive when subtracting, so what happens we subtract is that you can think of this sign change occurring: 
|dw:1342209418761:dw|