+118609 Try it this way.
Think of negative numbers as cold and positive numbers as hot.
So -- is taking away cold. What happens if you take cold away. It gets hotter.
So -- is +
REMEMBER it only works this way if the 2 minus signs ars do close together that you can put a circle around them with nothing else ion the circle.
3--7 = 3+7 = 10 
Look here
http://web2.0calc.com/questions/positive-and-negative-numbers-directed-numbers
a negative(-) and a negative(-) = a positive(+)
-,-=+
+,+=+
-,+=-
so its 3+7
which equals 10
+118609 Try it this way.
Think of negative numbers as cold and positive numbers as hot.
So -- is taking away cold. What happens if you take cold away. It gets hotter.
So -- is +
REMEMBER it only works this way if the 2 minus signs ars do close together that you can put a circle around them with nothing else ion the circle.
3--7 = 3+7 = 10
Look here
http://web2.0calc.com/questions/positive-and-negative-numbers-directed-numbers
