∣x-6∣+(y+7)×(y+7)=0
∣x-6∣+(y+7)×(y+7)=0
若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于
y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,
已知4x-3y-6y=0,x+2y-7z=0.求x-y+z\x+y+z的值
{2x+y/3-2y=0 2(2x+y)-5=7y
若x、y满足2x+y=6,x-3y=1,求7y(x-3y)²-2(3y-x)³的值
x-y=13 x=6y-7
X+Y=9 6X+7Y=59
若(x-2)的平方+15y-11=0,求代数式-3(2x-y)-{7x-[6x+2y-(10x-8y
若(x-2)*2+15y-11=0,求-3(2x-y)-{7x-〔6x+2y-(10x-8y)〕
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
(1){x+2y=0,3x+4y=6(2){5x+6y=16,7x-9y=5(3){9x-11y+1=0,4x-5y-3