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Find roots of z² - 4z + 5 = 0:

Az = 2 ± i
Bz = 2 ± 2i
Cz = 5 ± i
Dz = 1 ± 2i
Answer & Solution
Correct answer: A. z = 2 ± i
By quadratic formula: z = (4 ± √(16 - 20))/2 = (4 ± √(-4))/2 = (4 ± 2i)/2 = 2 ± i.
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