Answer:
x = - 2 ±
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Explanation:
Given
x² = - 4x + 3 ( add 4x to both sides )
x² + 4x = 3
To complete the square
add (half the coefficient of the x- term)² to both sides
x² + 2(2)x + 2² = 3 + 2²
(x + 2)² = 3 + 4 = 7 ← take the square root of both sides
x + 2 = ±
← subtract 2 from both sides
x = - 2 ±
← exact values