5X*0.15+9Y*0.2=0.18*(5X+9Y)解方程

5X*0.15+9Y*0.2=0.18*(5X+9Y)解方程 0.1x+0.3y = 0.15(x+y) 0.1x+0.3y+0.2×300 = 0.18×(x+y+300) x=?y=? 0.1x+0.3y = 0.15(x+y) 0.1x+0.3y+0.2×300 = 0.18×(x+y+300) x=?y=? 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 5x=3y,(2x+y)的平方=5x(x+y)+9 3x-2y=9 x-3y=2 x+y=5 x+2y=3 y=x 2x+y=8 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 『4x+9y=97 5x+5y=65』『0.2x+0.3y=4.6 0.7x-0.5y=0.6』 解方程组6(2/3x-2y)+5(x+0.2y+2)=9,3(x+y)-2(2x-y)=3 （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-y=110 9y-x=110 Y=x+3 7x+5y=9 y-x=3 7x+5y=-9 y=x+3 7x+5y=9 x y=5 x-y=9怎么解 x+y=5 x-y=9怎么解 {y=x+3,7x+5y+9;