Answer:

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Step-by-step explanation:

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The coordinates of B would be (2, -4)
In order to find this, we need to know that the value of M's points will always be the average of A and B's points. This is because it is the midpoint. Therefore we can use the following formula.
Value of x
(A + B)/2 = M
(-8 + B)/2 = -3
-8 + B = -6
B = 2
Then we can do the same for the y values
Value of y
(A + B)/2 = M
(-2 + B)/2 = -3
-2 + B = -6
B = 4
5/6 = .83333333333333333333333333.... It goes on...
.833333333333333333 * 18 = 15
15 is your answer
Another way you could do it is 18/6 = 3
3+3+3+3+3 = 15
3 being 1/6th of 18 *Hope This Helps...*
I believe the answer is cubic centimeter