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Error Analysis Kevin said that -2x(4x-3)=-8x²-6x. Karla said that -2x(4x-3)=-8x²+6x. Who is correct? Explain.

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Final answer:

Karla is correct in saying that -2x(4x-3) equals -8x² +6x, as distributing the -2x across the binomial results in a negative times a positive yielding -8x², and a negative times a negative yielding +6x.

Step-by-step explanation:

The student's question revolves around the process of distributing a negative value across a binomial and determining the sign of resulting terms. To clarify who is correct between Kevin and Karla, we distribute the -2x into the parentheses:


-2x(4x-3) = -2x × 4x + (-2x) × (-3)

  • For the first term, multiplying -2x by 4x gives us -8x² (because the signs are opposite).
  • For the second term, multiplying -2x by -3 gives us +6x (because we're multiplying two numbers with the same negative sign, resulting in a positive sign).

Therefore, Karla is correct: -2x(4x-3) = -8x² +6x.

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