2x² - 4x = 14
Divide by 2 through:
x² - 2x = 7
Add in the term (b/2)² :
x² - 2x + (2/2)² = 7 + (2/2)²
Complete the square:
(x - 1)² = 7 + 1
Combine like terms:
(x - 1)² = 8
Answer: (x - 1)² = 8
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The question did not ask to solve x. But here is the solution if needed to solve x:
(x - 1)² = 8
x - 1 = ±√8
x = 1 ±√+8
x =1 + 2√2 or x = 1 - 2√2
Answer: x =1 + 2√2 or x = 1 - 2√2