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2 years ago

(x – 2)^2 + 20 = 0

Mathematics

1 answer:

seraphim [82]2 years ago

7 0

Answer:

x = 2 ± 2 sqrt(5)i

Step-by-step explanation:

(x – 2)^2 + 20 = 0

Subtract 20 from each side

(x – 2)^2 + 20 -20=0 -20

(x – 2)^2 =- 20

Take the square root of each side

sqrt((x – 2)^2) =±sqrt(- 20)

x-2 = ±sqrt(- 20)

We know sqrt(ab) = sqrt(a) sqrt(b)

x-2 = ±sqrt(- 1) sqrt(20)

We know the sqrt (-1) = i

x-2 = ±i sqrt(4*5)

x-2 = ±i sqrt(4) sqrt(5)

Add 2 to each side

x-2+2 = 2 ±i sqrt(4) sqrt(5)

x = 2 ±i 2 sqrt(5)

x = 2 ± 2 sqrt(5)i

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Step-by-step explanation:

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Step-by-step explanation:

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Step-by-step explanation:

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