One reason that negative numbers would not make sense for values of the variables is that the solution having a negative value is not valid. It might be that the expression represents a real word problem and a negative value will not make any sense. Hope this helps.
Answer:
100
Step-by-step explanation:
because 4, 3, and 2 all make 180 and 4 and 2 are both 40 so you add that which makes 80 and then you take 180 and subtract 80 which gives you 100
Answer:
-392
Step-by-step explanation:
-56 x 7=-392
-392 / -56=7