8x+5y=13,4x-9y=-2

(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai 3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组, 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 联立方程 有的话 9y=3x-(x-1),4(x+y)-(2x+4)=8y 3x-2y=9 x-3y=2 x+y=5 x+2y=3 y=x 2x+y=8 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 2X+Y+Z=10,X+2Y+Z=-6,X+Y+2Z=8 5X+4Y-3Y=13,2X-3Y+7Z=19,3X-Y=2X 已知4x=9y求(1)x+y/y (2)y-x/2x 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 9x+8y=-2,4x+5y=-11,y最后等于多少