(340+y)/25=(646+y)/43=?
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
(x+y)(x+y+10)+25=0 x-y=3.求x,y的值
已知x=22/75,y=25/44,求(x+y)-(x-y)
x²+y²-6x+8y+25=0求(x-y)-²
已知(x-y)/13=y/7,则(x+y)/y=
解方程组(三分之x+y)+y=6,3(x+y)-y=24
化简求值:【(x+Y)(X-Y)-(X-Y)的平方+2Y(2-Y)】除4Y,其中X=1 Y=2
已知y²-3y+1=0,求下列分式的值 y²+(1/y²) y²/y的4次方+y
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
16(x-y)(x-y)-25(x+y)(x+y)=?x的4次方+4乘y的4次方=?因式分解,
微分方程y''-3y'+2y=5,y(0)=1,y'(0)=2求解过程
已知:3x=8y.求(1)x+y/y (2)2x+3y/x-2y