The number line graph of interval [10,-4] will be a straight line that runs from 10 to -4. The end points for 10 and -4 will be a coloured dot because the square brackets indicate that they are included in the number line. In contrast, while the number line graph of (10,-4) will also run in a straight line between 10 and -4, the end points at 10 and -4 will be uncoloured as it is not inckuded as suggested by the round brackets. 

Therefore, ( round brackets ) = not included = uncoloured dots

[ square brakets] = included = coloured dots

I hope this helps !