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33 votes
33 votes
Solve the equation x² + 6x + 1 = 0. give your answer to two decimal places

User Febin K R
by
2.5k points

1 Answer

14 votes
14 votes

Answer:

x ≈ - 5.83 , x ≈ - 0.17

Explanation:

x² + 6x + 1 = 0 ( subtract 1 from both sides )

x² + 6x = - 1

Using the method of completing the square

add ( half the coefficient of the x- term)² to both sides

x² + 2(3)x + 9 = - 1 + 9

(x + 3)² = 8 ( take square root of both sides )

x + 3 = ±
√(8) ( subtract 3 from both sides )

x = - 3 ±
√(8)

Then

x = - 3 -
√(8) ≈ - 5.83 ( to 2 dec. places )

x = - 3 +
√(8) ≈ - 0.17 ( to 2 dec. places )

User Prabhakaran S
by
2.9k points