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Solve (9^{2x + 1} = 81^{3x + 2})

Solve (9^{2x + 1} = 81^{3x + 2})

  • A.
    (frac{-3}{4})
  • B.
    (frac{-2}{3})
  • C.
    (frac{4}{5})
  • D.
    (frac{3}{2})
Correct Answer: Option A
Explanation

(9^{2x + 1} = 81^{3x + 2})

(9^{2x + 1} = (9^{2})^{3x + 2})

(9^{2x + 1} = 9^{6x + 4})

Equating powers, 

(2x + 1 = 6x + 4 implies -3 = 4x)

(therefore x = frac{-3}{4})