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(y+3) (y^2-3y+9) What is the product? y3 + 27 y3 – 27 y3 – 6y2 + 27 y3 + 6y2 + 27

a y3 + 27

b y3 – 27

c y3 – 6y2 + 27

d y3 + 6y2 + 27

2 Answers

2 votes
The correct answer is: [A]: " y³ + 27 " .
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Step-by-step explanation:
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(y + 3) (y² − 3y + 9) =

y*y² = y³

-3y *y = − 3y²

+9*y = + 9y
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= (y³ − 3y² + 9y) ;
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+3*y² = + 3y²

-9*y = − 9y

(+3)*(+9) = + 27
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= (3y² − 9y + 27) ;
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(y + 3) (y² − 3y + 9) =
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(y³ − 3y² + 9y) + (3y² − 9y + 27) =
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y³ − 3y² + 9y + 3y² − 9y + 27 = ?
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Combine the "like terms":
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y³ ;

− 3y² + 3y² = 0 ; [cancel out] ;

+ 9y − 9y = 0 ; [cancel out] ;

+ 27 ;
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to get:
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" y³ + 27 " ;
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→ which is: Answer choice [A]: " y³ + 27 " .
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User Asawilliams
by
8.5k points
3 votes
 A is the answer hope this helps
User Sapht
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8.4k points