x+3y/2=3/5 5(x-2y)=-4
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/17 01:26:10
x+3y/2=3/5 5(x-2y)=-4
x+3y/2=3/5 5(x-2y)=-4
x+3y/2=3/5 5(x-2y)=-4
小狗·LOVE
x+3y/2=3/5
5(x-2y)=-4
整理,得
10x+15y=6 ①
x-2y=-4/5 ②
②×10,得
10x-20y=-8③
①-③,得
35y=14
解得y=2/5
把y=2/7代入②中,得
x-2×(2/5)=-4/5
x-4/5=-4/5
x=4/5-4/5
x=0
∴此二元一次方程组的解是:x=0,y=2/5
因为x+3y/2=3/5 ,所以x=3/5-3y/2
代入5(x-2y)=-4 ,得:5(3/5-3y/2-2y)=-4
化简得:3-(35/2)y=-4
y=2/5
又因为x=3/5-3y/2
所以 x=0
y=2/5
x=6/5,y=1
式①*10
10x+15y=6③
式②
5x-10y=-4
式②*2
10x-20y=-8④
③-④
35y=14
y=2/5 x=0
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2
3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2
(x-y)/(x+y)=3求( 3x-2y-1)/(x+y-5)
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
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5
{(x+y)/2+(x-y)/3=1,(x+y)-5(x-y)=2.求x=?,y=?
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
先化简,再求值 [2/3x - 2/x+y(x+y/3x -x-y)]*x/x-y,其中5x+3y=0
(x+y-5)*(x+y-5)+(x-y+3)=0 x*x-y*y
先化简,再求值:[3x-2/x+y(x+y/3x-x-y)]/(x-y/x),其中5x+3y=0
已知:3x-5y=0,求x/y,x-y/y,x-y/x
3X=5Y (X+Y)*3X=(2Y+X)*4+2*2
5x=3y,(2x+y)的平方=5x(x+y)+9
3x+5y-(x+y)=6 2(x+y)-3x=-7