6. lg(2x - 1) · lg(1 - x) = 0 7. log₁₅₋₇ₓ (13 - 6x) = 1 8. log₂(-10x - 9) - log₂(5x + 4) = 3 9. log₃₂ (2 - x) + log₃₂(-x - 4) = ⅘