The answer is: "Answer choice: 1): "8x + 2y".
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Note: " 8 * x * 2 * y = 16xy ".
So, choice 3): "16xy is correct".
Choice 2): "16yx" is also correct, since: "16xy = 16yx".
Choice 1)": is incorrect, so this is the incorrect answer.
to be sure. let's plug in a values, "3" for "x" ; and "4" for "y";
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Choice 1) " 8x + 2y" ; 8(3) + 2(4) = 24 +8 = 32 .
Now, try: "16xy". 16(3)(5) = 48(5) = 240.
Note that: "32≠40" .
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So, Choice 1): "8x + 2y" ; is the correct answer.
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