Question

What is the coefficient of the second term of the trinomial?

Answer 1

The coefficient of the second term is 18.

What you do is you FOIL the terms:
$(3x+3)(3x+3)\\ Multiply\ the\ first\ terms\ together:\\ 3x*3x=9x^{2}\\ Then\ the\ outer\ terms:\\ 3x*3=9x\\ Next,\ the\ inner\ terms:\\ 3x*3=9x\\ Finally,\ multiply\ the\ last\ terms:\\ 3*3=9\\ Putting\ the\ terms\ together:\\ 9x^{2}+9x+9x+9=9x^{2}+18x+9\\\\ Since\ (3x+3)^{2}=9x^{2}+Bx+9=9x^{2}+18x+9,\ then \ B=18.$

Answer 2

Answer:  " 18 " .
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Explanation:
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  (3x + 3)²
 
 =   (3x + 3) (3x + 3)  ;
 
 =  Using "FOIL" method:  "First, Outer, Inner, and Last" terms ;
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First terms:  3x* 3x = 9x² ;
Outer terms:  3x * 3 = 9x ;
Inner terms:  3 * 3x = 9x ;
Last terms:   3 * 3 = 9 ;
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   So,  we have:  " 9x² + 9x + 9x + 9" ;
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      Combine the "like forms" to simplify further:
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          The "like terms" are:  + 9x + 9x = 18x ; 
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 Rewrite the expression:  
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          " 9x²  + 18x +  9 ";
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We want to find the coefficient of the second term in the trinomial given:
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          " 9x² + <span />Bx + 9 "  ; 
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The coefficient of the second term in this polynomial is: "B" ;
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                B = 18 .
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The answer is:  " 18 " .
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