Solve x² − 2x − 4 = 0.
A1 ± √5
B2 ± √5
C−1 ± √5
D−2 ± √5
Answer & Solution
Correct answer: A. 1 ± √5
D = 4 + 16 = 20. x = (2 ± √20)/2 = (2 ± 2√5)/2 = 1 ± √5.
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