Question

What is - x-x is equal to?

Answer 1

Which means, change the minus to a plus, and change the positive x to a negative x. 
(+x) + (-x). 
Maybe now it is easier to see? 
It equals 0 

Answer 2

Answer:

$Simplification \: of \: -x-x = -2x$

Step-by-step explanation:

$Simplification \: of \: -x-x \\=-1x-1x\\ = (-1-1)x\\=-2x$

Therefore,

$-x-x = -2x$

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