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If log₁₀ ( x² - 6x + 45 ) = 2, then the values of x are

1. 6, 9
2. 9, −5
3. 10, 5
4. 11, −5

Correct Option: D

Given that : - log₁₀ ( x² - 6x + 45 ) = 2
⇔ x² - 6x + 45 = 10² = 100
⇔ x² - 6x - 55 = 0
⇔ ( x - 11 ) ( x + 5 ) = 0
⇔ x = 11 or x = - 5.
Hence , the values of x are 11 and - 5.