=8x + (-3) (5) + (-3) (9x)
=8x + -15 + -27x
=8x + -15 + -27x
(8x + -27x) + (-15)
19x +-15
19x -15
The answer is: [A]: He did not apply the distributive property correctly for 4(1 + 3i) .
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Explanation:
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Note the distributive property of multiplication:
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a*(b+c) = ab + ac.
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As such: 4*(1 + 3i) = (4*1) + (4*3i) = 4 + 12i ;
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Instead, Donte somehow incorrectly calculated:
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4*(1 + 3i) = (4*1) + 3i = 4 + 31; (and did the rest of the problem correctly);
Note: - (8 - 5i) = -8 + 5i (done correctly;
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So if Donte did not apply the distributive property correctly for 4*(1+3i)—and incorrect got 4 + 3i (as mentioned above); but did the rest of the problem correctly, he would have got:
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4+ 3i - 8 + 5i = -4 + 8i (the incorrect answer as stated in our original problem.
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This corresponds to: "Answer choice: [A]: <span>He did not apply the distributive property correctly for 4(1 + 3i)."
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