-5 x 3 = -5 + (-5) + (-5) = -15 

  The rule is a positive number multiplied by a negative number will give you an answer that is negative.  6 x (-7) = -42 and   -7 x (6) = -42 

      Why don't I have to put the negative 7 in parentheses ?  I did in 6 x (-7) = but not in -7 x 6 = Why?  return