7x+6y=335x-4y=7

7x:4y,x:y=( ):( (x-y)的4次方/(y-x)的3次方+(x-y)0的次方*(y-x)+(-x-y)7次方/(x+y)6次方= {6(x-y)-7(x+y)=21 {2(x-y)-5(x+y)=-1 把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)= 3(x-y)把(x-y)看作一个整体,化解:5(x-y)+2(x-y)-4(x-y)=3(x-y)²-4(x-y)+7(x-y)-6(x-y)²= 若(x-y)/(x+y)=3 则(x+2y)/(6x-7y)等于 把(x-y)看做一个整体,合并同类项5(x-y)+2(x-y)-4(x-y)=3(x-y)次方-4(x-y)+7(x-y)-6(x-y)次方= 已知x+y=6,xy=7,试求x*x+y*y,x*x-y*y的值 (x-y)(x-2y)+(x-2y)(x-7y),其中X=4,Y=1.5 计算3x/(x-3y)+(x+y)/(4y-x)-7y/(x-4y)=? 大括号x+y/2+x-y/3=11/6 4(x+y)-5(x-y)=7 快 初二上学期方程题 4x+y=5 5x+4y=63x-2y=1 2x+3y=13x-2y=7 7x+5y=32x+3y=17 2x-y=-4x+5y=6 2x+y=23x-6y=4 3x+2y=52x+y=73x-4y=53x+y=1x-2y=-1x+y=42x+3y=92x-3y=74x+5y=3x+y=20004x+6y=90003x+5y=113x-2y=42x+3y=215x-2y=5x+y=54x+3y=182x+3y=16x+4y=132x+3y=40x 4y-/2=-6x 2y 3x=7-2x-y 已知|5x-y-8|+(7y-x+2)=0则4x+6y x y为正实数 x+y=6 求x+4/(7-y)的最小值 已知：2x+y=6,x-3y=1 求7y(x-3y)(x-3y)-2(3y-x)(3y-x) 若7x+6(x-y)=-4,3x-4(y-x)=18,则x-y=__ 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 联立方程 有的话