Answer:
(b) 4a³
Step-by-step explanation:
The value of B is the sum of the a-cubed terms:
12a³ -6a³ -2a³ = (12 -6 -2)a³ = 4a³ . . . . . matches the 2nd choice
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Additional comment
A = (-2a)(-2a) = 4a²
