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圓x²+y²+x-6y+3=0上兩點P、Q關于直線kx-y+4=0對稱，則k=

圓x²+y²+x-6y+3=0上兩點P、Q關于直線kx-y+4=0對稱，則k=______.

圓x²+y²+x-6y+3=0上兩點P、Q關于直線kx-y+4=0對稱，則k=______.

圓x²+y²+x-6y+3=0上兩點P、Q關于直線kx-y+4=0對稱,則k=__________.

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