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Solve x^2 + 4x + 8 = 0

User Selina
by
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1 Answer

5 votes

Answer:

x = -2 + 2 i or x = -2 - 2 i

Explanation:

Solve for x:

x^2 + 4 x + 8 = 0

Subtract 8 from both sides:

x^2 + 4 x = -8

Add 4 to both sides:

x^2 + 4 x + 4 = -4

Write the left hand side as a square:

(x + 2)^2 = -4

Take the square root of both sides:

x + 2 = 2 i or x + 2 = -2 i

Subtract 2 from both sides:

x = -2 + 2 i or x + 2 = -2 i

Subtract 2 from both sides:

Answer: x = -2 + 2 i or x = -2 - 2 i

User Dmytro Biletskyi
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