4y+3x=5 .-x+2y=-5 怎么解这个二元一次方程 用代入消元法

二元一次方程(x+y)/2+(x-y)/3=6,4(x+y)-5(x-y)=2怎么算 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 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 3x+2=y 5x+4=y 7x+6=y 9x+8=y 11x=y怎么解 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 5x+4y=22 4x+y=3y+x 怎么解 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian {2X=5(X+Y)3X-10(X+Y)=2怎么解? 3X=5Y （X+Y)*3X=(2Y+X)*4+2*2 3x*5y+2x*6y=2.7*(3x+2x)怎么解 三元一次方程组x-2y=5,4x-y+3z,2x+y=0怎么解 （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x （5x+3y)(3y-5x)-(4x-y)(4y+x)= x*x+2x+y*y-4y+5=0 x= y=