Answer:
C. 
Step-by-step explanation:
I think the equation meant
?
Anyways, to factor these kinds of quadratic, keep into consideration:

ONLY if:

Start off by finding factors of c, which in this case, -18:
±(1, 2, 3, 6, 9, 18)
If one of the numbers is negative then the other number must be positive.
Find which two factors will sum up to b, which in this case, is 3.

The only two factors that work are 6 and -3.
Replace them into the factored form:

First, find the surface area of the bigger sides (there are 4 of them so what you get for one you will multiply by 4)
12 x 8 = 96
96 x 4 = 384
Then find the surface area of the smaller sides ( there are two small sides so multiply your answer by two)
8 x 8 = 64
64 x 2 =128
Then add both together
128 +384 = 512
Hope this helps :)
Hello,

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