Respuesta :

the sum of 3 terms..." sum " means add

x + 3 + x <==
The correct answer is:  [D]:  " x + 3 + x" .
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The three (3) terms are:  "x" , "3" , and "x" .
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Answer choice  [A]:  "3x" ;  only has one term.
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Answer choice  [B]:  "x + 3 " ; only has two terms:  "x" and "3" .
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Answer choice  [C]:  "x³ " ; only has one term.
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