multiply -7 (2a square minus 4) how do i work the problem?

im doing basic concepts in algebra and i need to how to solve this pronlem

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lemonie7 years ago
To do as Kiteman advised you, this is your answer:
-7(2a2-4)
is
-14a2+28

L

Its a style thing, but I don't like hanging minus signs, so I always write
28-14a2
I'd prefer that too, but I was doing a "literal" there.

L
kelseymh7 years ago
Orksecurity has it almost right.  The =word you need to know is associativity.  Here's a hint:  a × (b + c) = a×b + a×c. 
Thanks for the correction.
Kiteman7 years ago
For this specific example, multiply each thing inside the brackets by each thing outside the brackets.

Beware of your signs.
orksecurity7 years ago
Transitivity and commutivity.  Think about how you might do it if a was a specific number but you weren't allowed to subtract 4 before doing the multiplication.