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9 x² - 6 x + 1 = x² + 6 x + 9
9 x² - x² - 6 x - 6 x = 9 - 1
8 x² = 8
x² = 1
x = √1
x² + 2 x + 1 - 9 x² - 3 x = 0
- 8 x² - x + 1 = 0
x ( - 8 x - 1 + 1) = 0
x ( - 8 x ) = 0
x = 0
9 x² - 6 x + 1 = x² + 6 x + 9
9 x² - x² - 6 x - 6 x = 9 - 1
8 x² = 8
x² = 1
x = √1
x² + 2 x + 1 - 9 x² - 3 x = 0
- 8 x² - x + 1 = 0
x ( - 8 x - 1 + 1) = 0
x ( - 8 x ) = 0
x = 0