You could solve all the equations to see if a letter matches the question's request if you're into trail and error. Simply multiply each integer in one pair of parentheses by each individual in another, a box could help you with this (like a box in third grade showing what numbers shown on one side multiplied by numbers on the intersecting side are)
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The answer: If you're looking for the answer, continue below
The answer would be "B";
(x-2)(x^2+2x+4) could be rearranged into..
-2(x^2+2x+4) + x(x^2+2x+4) when, when distributed is..
(-2x^2-4x-8) + (x^3+2x^2+4x) which is then added..
x^3+8
There was some additional simplifying and adding, but you should understand it.
I’m pretty sure it’s 13. Def not 10
H= -1
Distribute:
-(4+h)= -4 - h
-4 - h= 3h
-4 +h = 3h + h
-4= 4h
-1 = h
Factor ouf 3x
3x(12x^2-5x-2)
factor
(3x)(3x-2)(4x+1)