{6x+5y=25 3x+4y=20
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
5(x-y)^3*[-6/25(y-x)^3][-2/3(y-x^4]=
已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值
已知/6x+5y-25/+(3x+4y-20)(3x+4y-20)=0,求x,y的值.
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
(5x+3y)(3y-5x)-(4x-y)(4y+x)=
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
{4/(x+y)+6/(x-y)=3 {9/(x-y)-1/(x+y)=1
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
4x-2y-6y*-y-3x+5y* *=2 就是平方