25X+12Y=7 10X-18Y=-4 3X+8Y=26 5X-12Y=37

25X+12Y=7 10X-18Y=-4 3X+8Y=26 5X-12Y=37 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 （5x+3y)(3y-5x)-(4x-y)(4y+x)= 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X 解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3 解方程组：x+y/2+x-y/3=6 4(x+y)-5(x-y)=12 (x*x+y*y)(x*x+y*y)-(x*x+y*y)=12 求x*x+y*y等于多少 已知x.x+y.y-6x-8y+25=0,求3x.x+5y的值 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y除以2x-y 已知2x-y/x+3y=2,求代数式4x-2y/x+3y减4x+12y/2x-y的值