{5x+6y=8 2x-6y=-1

{6(x-y)-7(x+y)=21 {2(x-y)-5(x+y)=-1 {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 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= (x+y)/6+(x-y)/10=1,(x+y)/6-(x-y)/10=5 x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2 6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5 2(x+y)-3(x-y)=1 6(x+y)+(x-y)=51 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 例X=1 y=21.X+Y=5 X-Y=15 2.2X+3Y=4 5X+6Y=7 3.X+3Y=5 3X+Y=-1 4.2X+Y=3 3X+5Y=11 5.4X+3Y=6 2X+Y=4 6.X+Y=180 X=3Y-10 7.3X-2Y=3 2X-Y=7 8.5X+3Y=7Y X+Y=45 9.3X+4Y=126X+8Y=24 X:6Y=1:4 10.X+Y=138 X-45=Y+53 11.X+Y=60 14Y=20X 12.2X+3Y=15.5 5X+6Y=35 13.X+Y=170 3 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 5x+y=6 2x-y=1 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 解一些方程组8(1/x+1/y)=16/x+x/y=19/(x+y)+6/(x-y)=312(x+y)=12(x-y)-11/(2x+y)-1/(x-2y)=53/(2x+y)-2/(x-2y)=5过程可以省略. y=6x 4：x=0.5:y y=x y=2:8 y=5x+1怎样算? x+y/2+x-y/3=5/6;x=y/6-x-y/3=1/2 3(2X+Y)+(2(2x-Y)=6 (8X+4y)-(10X-5Y)=2 y-x/7-x+y/6=1/2 5(x+y)-2(y-x)=1怎么解答