方程组：{2x-y+5=0,2x+4y=10.

解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7 方程组x-2y=8,3x-4y=5,x=?,y=? 解方程组3x+5(x+y)=2 3y-2(x+y)=4 方程组4x+y=3 3x+2y=5,则x-y= y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组,无 把方程组(x+y)(x-2y)=0 x方+y方=5化为两个两元二次方程组 解方程组x^2-y^2=x+y 4x^2-y^2+2x-y=0过程 解方程组 x+y/5+x-y/2=7 4(x+y)-5(x-y)=2 二元一次方程组(x+y)/2+(x-y)/2=6,4(x+y)-5(x-y)=2 解方程组 X+Y/2+X-Y/3=6 4[X+Y]-5[X-Y]=2 解二元一次方程组{x+y/2+x-y/3=6,4(x+y)-2=5(x-y) 解方程组2分之x+y+3分之x-y=6 4(x+y)-5(x-y)=2 解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4 解方程组x+y/2+x-y/2=7,4(x+y)-5(x-y)=2... 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组 x+y/2+x-y/3=6,4(x+y)-5(x-y)=2用加减消元法解方程组 如果方程组x-y=a-3,2x+y=5的解x、y满足x>0,y 解方程组 {3(x+y)-4(x-y)=11 {2(x-y)+5(x+y)=27