2x-y-2=0 4x-3y-8=0 用加减消元法做

{x+y=1 ,xy=-6{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 解下列方程组：{x(2x-3)=0,y=x²-1{(3x+4y-3)(3x+4y+3)=0,3x+2y=5{(x-y+2)(x+y)=0,x²+y²=8{(x+y)((x+y-1)=0,(x-y)(x-y-1)=0 x*x+2x+y*y-4y+5=0 x= y= y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,无 已知(3x+1)(3x-3)-3x+2)^2=-7,(y+7)(y-7)-y(y-7)=0,求8y^2-5y(-y+3x)+4y(-4y-5/2x)的值 {4x-3y-10=0 3x-2y=0,{3x-4(x-y)=2 2x-3y=1,{2(x+y)-(x-y)=3 (x+y)-2(x-y)=1 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 已知x^2-8x+y^2-y+16又1/4=0,求[(x+y)(x-y)-(x+y)^2-2y(x-3y)]÷4y的值 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 已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的值 若x-y不等于0,2x-3y=0,则分式(10x-11y)/(x-y)的值是（）?(10x-11y)/(x-y) =[(8x-8y)+(2x-3y)]/(x-y) =8为什么8X-8Y=8？(10x-11y)/(x-y)=[(8x-8y)+(2x-3y)]/(x-y)=8+(2x-3y)]/(x-y)=8+0=8 若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*y)的值 x-2y+3=0 求x^2-(4y+1)x+4y^2+8y 已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? x^2+4y^2-6x+4y+10=0,求x^4-y^4/(x+2y)(x-2y)*x+2y/xy^2+y^3除以（x^2+y^2/y)^2的值 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)=