x+y=180 x/12+y/8=20x+y=180x/12+y/8=20

x+y=180 x/12+y/8=20x+y=180x/12+y/8=20 x+y=18 x/12 +y/8 =20 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 12y(x-y)^2-8(x-y)^3=? 化简 x / y(x+y) - y / x(x+y) = x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 y=x(x (x*x+y*y)(x*x+y*y)-(x*x+y*y)=12 求x*x+y*y等于多少 x+x+x+y=20 x+x+y=14 x=?y=? Y-X=45 (85%Y-X)×8=(Y-35-X)×12 Y-X=45 (85%Y-X)×8=(Y-35-X)×12 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) x.y都是自然数,且x(x-u)-y(y-x)+12,求x.y得值快1且x(x-y)-y(y-x)=12 例X=1 y=21.X+Y=5 X-Y=15 2.2X+3Y=4 5X+6Y=7 3.X+3Y=5 3X+Y=-1 4.2X+Y=3 3X+5Y=11 5.4X+3Y=6 2X+Y=4 6.X+Y=180 X=3Y-10 7.3X-2Y=3 2X-Y=7 8.5X+3Y=7Y X+Y=45 9.3X+4Y=126X+8Y=24 X:6Y=1:4 10.X+Y=138 X-45=Y+53 11.X+Y=60 14Y=20X 12.2X+3Y=15.5 5X+6Y=35 13.X+Y=170 3 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= x+x+x+x+y+y+y=56 3x-20=y x+y=180 y+y+x=10,x+y+x=8,y=?,x=?