x²+y²-4x-6y+13=0x²-4x+4+y²-6y+9=0(x-2)²+(y-3)²=0x=2 y=3 （- y/x^3)^3÷(- 1/xy)^4.(x/y^2)^2=-y^3/x^9 * x^4y^4*x^2/y^4=-y^3/x^3=-(y/x)³=-（3/2）³=-27/8如果本题有...