Answer:
-30
Explanation:
it is adding 10 three times, but then you add the negative after
so it is 10+10+10 because you are multiplying it by 3
you could also add 3 ten times because the communitive property
so 3+3+3+3+3+3+3+3+3+3
you would do the same whether the -3 was in parentheses or not