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Solve x2 + 4x − 4 = 0
Answer Choices:
x = -2 ± √16 all over 2
x = -4 ± √2
x = -2 ± 2 √2
x = 4 ± √18 all over 2

Respuesta :

Answer:

third option

Step-by-step explanation:

Given

x² + 4x - 4 = 0 ( add 4 to both sides )

x² + 4x = 4

Using the method of completing the square

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

x² + 2(2)x + 4 = 4 + 4, that is

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

x + 2 = ± [tex]\sqrt{8}[/tex] = ± 2[tex]\sqrt{2}[/tex] ( subtract 2 from both sides )

x = - 2 ± 2[tex]\sqrt{2}[/tex]

The answer is the third choice