1.｛2X-3Y=8 2.｛9X+8Y=-2 3.｛3(x-1）=Y+5｛3X+7Y=0.5 ｛4X+5y=-11 ｛5(y-1)=3（X+5）4.｛3分之2U+4分之3V=2分之1｛5分之4U+6分之5V=15分之7

【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= 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 12y(x-y)^2-8(x-y)^3=? 方程组1.{x+y+1=0,x^2+4y^2=8 2.{(x-3)^2+y^2=9,x+2y=0 3.{x+y=6,xy=7方程组1.{x+y+1=0,x^2+4y^2=8 2.{(x-3)^2+y^2=9,x+2y=03.{x+y=6,xy=7方程组1.{x+y+1=0,x^2+4y^2=8 2.{(x-3)^2+y^2=9,x+2y=0 3.{x+y=6,xy=7 1.（（y+2x)(-2x+y)+4(x+2y)^2)/3y 2.（2(x-y)^3-8(x-y）^2(x+y)+6y(x-y)^2）/2（x-y)^2 1.（－2a）³·b²÷(8a³b²) 2.－5x（2x²－3x＋4）+4x³+15x3.（x²-2y²）(x+2y)-2xy(x-y)4.（x-y+z）(x-y-z)化简求值 ［（x+y）(x-y)-(x+y)²-2y(x-2y)］÷(-2y),其中x=5,y=2003 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 1.已知二元一次方程3X+4Y=6,当X,Y互为相反数,X=?Y=?当X与Y相等,X=?Y=?2.{Y=3/2X 3{3X-Y=5 4.{5X+Y=32X+8Y=22 5X+3Y-13=0 2X+3Y=-10.55.{X+1=5（Y+2）3（2X-5）-4（3Y+4）=53-5题用代入法解方程组2.{Y=3/2X 2X+8Y=223{3X-Y=55X+3Y-13=0 （x+y)+(2x+1/1*2y)+(3x+1/2*3y)+.+(9x+1/8*9y) x=2 y=90求和 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 联立方程 有的话 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y 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怎么解 y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,无 化简(x+y)+(2x+1/2y)+(3x+2/3y)+(4x+3/4y)+...+(9x+8/9y)=? 化简：(-4x+3y)(-3y-4x)-(2x+3y)(8x-9y),其中,x=-3,y=-2 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX..