21ab-14ac+28a you just times everything in the parenthesis by the stuff outside the parenthesis
21ab-14ac+28 is the answer
The expression 7 a ( 3 b − 2 c + 4 ) simplifies to 21 ab − 14 a c + 28 a by distributing 7 a to each term inside the parentheses. The individual products are then combined to form the final result.
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