The problem is (-3) · (2) · (-2)
You know that when you're doing multiplication, the order
doesn't matter. So let me line up the factors like this:
(-3) · (-2) · (2) .
Multiply the first two of them: (-3) · (-2) = +6
(The product is positive because
both factors have the same sign.)
Now multiply that result by the last factor: (6) · (2) = 12 .
What was so hard about that ?