8X - 6X = -18
2X = -18
X = -9.
Hope this helps!
What was the original container?
Answer:

Step-by-step explanation:

After removing one black marble:

Answer:
The width is 2.
Step-by-step explanation:
The equation is 2 x 3 x ? = 12.
It is 2 long
It is 3 in height
2 x 3 = 6
6 x 2 = 12
so 2 is the width.
Answer:
neither
Step-by-step explanation: