解方程组{2x-3y=7、x-3y=7

解方程组3分之x-y=2分之 x+y解方程组3分之x-y=2分之 x+y；2x-5y=7 解方程组x+y/5+x-y/7=2 3(x+y)+x-y/7=16 2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组 解方程组﹛2(x+y)-3(x-y)=1 6(x+y)+7(x-y)=51 解方程组8y+5x=84y-3x=7 方程组 因式分解 4x^3-4x^2y-(x-y) 解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 解方程组 3x-5y=7 4x+2y=5解方程组3x-5y=74x+2y=5 已知方程组(x+y)-3(x-y)=7 解方程组 y=2x x+y=3 解方程组解方程组｛y=2x-7｛x+y+z=1｛3x-z=4 解方程组{ (x-y)/3=(x+y)/2 { 2x-5x=7解方程组{ (x-y)/3=(x+y)/2{ 2x-5x=7{2x-5y=7 解方程组{（x+2）^2-(y-3)^2=(x+y)(x-y) {x-3y=2 解方程组{3x+2y=7 {2x+3y=18解不等式组{x-2 已知方程组{2x+y=6,x-3y=1,不解方程组,求7y(x-3y)²-(3y-x)²的值.已知方程组{2x+y=6,{x-3y=1.不解方程组,求7y(x-3y)²-(3y-x)²的值.已知方程组{2x+y=6，{x-3y=1.不解方程组，求7y(x-3y)²-(3y-x)³ 解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3 二元一次方程组 X-Y/7-X+Y=0.5 2(X-Y)+5(X+Y)=3 已知方程组{(X+Y)-3(X-Y)=7,2(X+Y)+(X-Y）=-7}则(X+Y)(X-Y)= 已知方程组2X+Y=6和X-3Y=1不解方程组,求7Y(X-3Y)^2-(3Y-X)^3 用代入法解此方程组：（x+y)/2+(x-y)/3=6 4(x+y)-5(x-y)=2求方程组的正整数解：x+y+z=7 2x+3y+4z=20