Answer :
9 because anything in the absolute value signs can't be negative, so it would be 6 + 3 = 9
[tex]|a|= \left\{\begin{array}{ccc}a&if\ a\geq0\\-a&if\ a < 0\end{array}\right\\\\|-3|=3\\|\ 0\ |=0\\|\ 6\ |=6\\|-100|=100\\\\\\|-6|+|\ 3\ |=6+3=9[/tex]
