x²+y²-8x-10y+41=0(x²-8x+16)+(y²-10y+25)=0(x-4)²+(y-5)²=0x-4=0,y-5=0x=4,y=5x/y-y/x=4/5-5/4=-9/20
x²+y²-8x-10y+41=0,x^2-8x+16+y^2-10y+25=0(x-4)^2+(y-5)^2=0平方都大于等于0相加为0则各项均为0所以x-4=0y-5=0所以x=4,y=5原式=4/5-5/4=-9/20