Which property of addition is shown here? If x is equal to 1 plus 2 i and y is equal to negative 1 minus 2 i , then x plus y is equal to 0

Substitute the values: x + y = (1 + 2i) + (−1 − 2i). The real parts, 1 and −1, add to 0, and the imaginary parts, 2i and −2i, also add to 0. Each number is the additive inverse of the other, so their sum is 0; this is the inverse property.

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