3X—2X+4Y=3 11X+4X+8Y=45二元一次方程组,

3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 9y=3x-(x-1),4(x+y)-(2x+4)=8y x^3+2x^2y-4x-8y 2（x+y)-3(x-y)=3 ,4(x+y)+3(x-y)=15 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 4x-3y/x-2y÷6y-8x/y-2x 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 （x+y）/2- x-y/2=6 3(x+y)=4(x-y) x+y/3+x-y/2=6 4(x+y)-2(x-y)=40 根据3（x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y= (x+y)(x+2y)(x+3y)(x+4y)=-40y的值为根号11