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bulgar [2K]
4 years ago
13

Complex numbers x^2-4x-21=0​

Mathematics
1 answer:
kolezko [41]4 years ago
5 0

Answer:

x = -3, 7

Step-by-step explanation:

x² - 4x - 21 = 0

factor (what multiplies to -21 and adds to -4?):

3 and -7

(x + 3)(x - 7) = 0

zero product property:

x = -3, 7

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