13X+11Y=1240,

{x=y-3 {x+y=11 {2x+y=13 {3x-2y=8 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 (1)2X-Y=1 3X-2Y =1 (2)4X-3Y=11 2X+Y=13 (3)3X+Y=1 1/2X+1/4Y=0 1.{x=y-3 {2x+y=13 2.{x+y=11 {3x-2y=8 1,{3x+2y=13 {5x-2y=11 ,2,{5x+2y=25 {3x+4y=15 1,{3x+2y=13 2,{5x+2y=25 {5x-2y=11 {3x+4y=15 已知3x-2y=6,2x-3y=17,6x^2-13xy+6y^2-24x+11y-90=? 解方程组27/(3X-2Y)-2/(-2X+3Y)=1 18/(3X-2Y)+11/(2X-3Y)=13 已知x+y/y=11/8,求x-y/x+2y的值. 已知x+y/x=11/8,求x-y/x+2y的值 1.x+x+x+y+y=6.4 y+y+y+x+x=7.1 x= ( ) y=( ) 2.1,4,7,10,13……这串 已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的