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圓x²+y²+x-6y+3=0上兩點(diǎn)P、Q關(guān)于直線kx-y+4=0對(duì)稱，則k=

圓x²+y²+x-6y+3=0上兩點(diǎn)P、Q關(guān)于直線kx-y+4=0對(duì)稱，則k=______.

圓x²+y²+x-6y+3=0上兩點(diǎn)P、Q關(guān)于直線kx-y+4=0對(duì)稱，則k=______.

圓x²+y²+x-6y+3=0上兩點(diǎn)P、Q關(guān)于直線kx-y+4=0對(duì)稱,則k=__________.

圓x²+y²+x-6y+3=0上兩點(diǎn)P、Q關(guān)于直線kx-y+4=0對(duì)稱，則k=