9x^2+4y^2+______=(3x+2y)^2
若3x-4y=0,则x/y=______,(x-y)/y=______,(3x+2y)/(2x+3y)=_____.
9x^2+4y^2+______=(3x+2y)^2
已知2x+3y=5,则6x-4y-2(x-5y)=______.
若x+3y=3x+2y=7,则x=______,y=______.
9y=3x-(x-1),4(x+y)-(2x+4)=8y
若2x-3y=5,则6-4x+6y=______.
已知4x=9y求(1)x+y/y (2)y-x/2x
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27