X+Y=5.7 1/4X+2/5Y=4/5X 怎么解
X+Y=5.7 1/4X+2/5Y=4/5X 怎么解
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1
5x+4y=22 4x+y=3y+x 怎么解
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
解方程组:(0.2x+0.1y)/2- (4x-y)/10=(x-y)/5+ (3x+0.5y)/30 (3x+2y-1
5x+4y=6 2x+3y=1二元一次方程怎么解
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
解方程组{x=2y,x+y=3; {y=1-x,3x+2y=5 ;{3x+5y=5,3x-4y; {2分之x-3分之y+