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If x = (10 − 3i) and y = (3 − 10i), then

A. (x + y = 13 - 13i)
B. (x + y = 13 - 7i)
C. (xy = 69 - 149i)
D. (xy = 69 + 149i)

User Curlas
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1 Answer

3 votes

Final answer:

The value of x+y is 13 - 13i and the value of xy is 69 - 109i.

Step-by-step explanation:

The question asks for the value of x+y and xy given that x = (10 − 3i) and y = (3 − 10i).

To find x+y, we add the real parts and the imaginary parts separately. So, x+y = (10 + 3) − (3 + 10)i = 13 - 13i. This means option A (13 - 13i) is correct.

To find xy, we use the distributive property. So, xy = (10 − 3i) * (3 − 10i) = 30 - 100i - 9i + 30i^2 = 30 - 109i - 30 = 69 - 109i. This means option C (69 - 149i) is correct.

User Pmk
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