x-y=13X=6Y-7
x-y=13 x=6y-7
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X
1.x+x+x+y+y=6.4 y+y+y+x+x=7.1 x= ( ) y=( ) 2.1,4,7,10,13……这串
已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的
【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2=
X+Y=9 6X+7Y=59
x+y=3 x+2y=9 3/x+1=y y-x=3 y=2x-3 y-3x=1 2(x+1)-y=6 7x-5y=-9
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
已知x,y满足:x平方+y平方-4x+6y+13=0求(3x+y)-3(3x-y)(x+y)-(x-3y)(x+3y)=
已知(x-y)/13=y/7,则(x+y)/y=
已知x*x+y*y-4x-6y+13=0,求3x+4y的值