3x+4y=18,2x-3y=-5
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/27 10:02:39
3x+4y=18,2x-3y=-5
3x+4y=18,2x-3y=-5
3x+4y=18,2x-3y=-5
3x+4y=18 (1)
2x-3y=-5 (2)
(1)×3+(2)×4
9x+12y+8x-12y=54-20
17x=34
所以
x=2
y=(2x+5)/3=3
(3x+4y)*2=18*2
(2x-3y)*3=-5*3
17y=51
y=3
x=2
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
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) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)=
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(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
3X=5Y (X+Y)*3X=(2Y+X)*4+2*2
(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)=
2(x+y)-3(x-y)=3 ,4(x+y)+3(x-y)=15
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20
4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6
3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9
x+y/2+x-y/6=5 2(x+y)-3(x-y)=-2