一道2元2次方程组.x^2 - 5*x + y^2 - 2y =0{(x-5)^2 - (y-2)^2= x^2+ y^
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
3元1次方程组 x+y-z=4 (1) 2x-y=5-x (2) x-3y+z=-2 (3)
2x-3y=4,5x+6y=7的2元1次方程组怎么解?
解3元1次方程组3元1次方程组2x+3y=10x+z=5z+y=7.5
一道二元一次方程组!3(x+y)-4(x-y)=4,(x+y)/2+(x-y)/6=1
方程组 x+5y+2=06x-7y=16x=y=
方程组x-2y=8,3x-4y=5,x=?,y=?
如果2元1次方程组x+y=a,x-y=4a的解是2元1次方程组3x-5y-30=0的1个解,a=?
换元法解方程组3/x+y+2/x-y=17/5 2/x+y-5/x-y=1
x+y/2+x-y/3=6,4(x+y)-5(x-y)=2用加减消元法解方程组
3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 解方程组
解方程组 {(x+y)/2+(x-y)/3=6 5(x+y)-2(x-y)=4