Donte simplified the expression. 4 times open paren 1 plus 3 i close paren minus open paren 8 minus 5 i close paren 4 plus 3 i minus 8 plus 5 i negative 4 plus 8 i What mistake did Donte make?

Distribute 4 to both terms inside the first parentheses: 4(1 + 3i) = 4 + 12i, not 4 + 3i. The subtraction before (8 − 5i) changes its signs, so the expression becomes 4 + 12i − 8 + 5i = −4 + 17i. Donte’s mistake was not applying the distributive property correctly to 4(1 + 3i).

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