- 若2y-5x=0,则x:y等于( )A.2:5B.4:25C.5:2D.25:4
- 已知ab=3,则a-bb=______.
- 若x:y:z=2:3:4,则3x+2y-zx+y+z=______.
- 若x3=y4=z5,则x+y+zz=______;若x-yy=12,则xy=______.
- 已知:x2=y3=z4=k,且2x-3y+z=10,则x+y+z=( )A.90B.-90C.70D.-70
- 已知:a2=b3=c4,求b-ab+c的值.
- 若2y-3x=0,则x:y等于( )A.3:2B.4:9C.2:3D.9:4
- 已知:y+zx=x+zy=x+yz=k,则k=______.
- 如果x与y存在3x-4y=0的关系,那么xy=______,x-yx+y=______,x+yy=______.(ba≠0)
- 已知线段a,b,c,若a2=b3=c5,且3a-2b+5c=25,则a=______,b=______,c=______.
- 若x:y:z=3:5:7,3x+2y-4z=9,则x+y+z的值为( )A.-3B.-5C.-7D.-15
- 已知x2=y3=z4≠0,求x-4y+3zx+4y-3z的值.
- 若m-nn=34,则nm=______.
- 已知x3=y4=z5,求x+yx-2y+3z的值.
- 若a-bb=43,则ba=______.