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x2 + 4x + 1 = 0 add and subtract 3 to both sides to complete the square

x2 + 4x + 4 = 3 form the square

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

x + 2 = ± √3 subtract 2 to both sides

x = -2 ± √3

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11y ago
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15y ago

we alweeys add (1/2 cofftiant of x )2 (1/2*4)2 =4

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Q: How do you solve x2 - 4x 1 0 by completing the square?
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