Question

解下列方程x+2/5=x/4;1/4(x+1)=1/3(x-1);2x-1/3=x+2/4-1;1/2(x-1)=2-1/5(X+2).

Answer 1

，x=-8/15；x=7；，估2x-1/3=（x+2）/4-1，x=-2/21，x=-1/6；x=3

Answer 2

x+2/5=x/4
x-x/4=-2/5
3x/4=2/5
x=8/15

就是这样

Answer 3

x+2/5=x/4 1/4(x+1)=1/3(x-1)
4(x+2)=5x 1/4x+1/4=1/3x-1/3
4x+8=5x 1/4x-1/3x =-1/3-1/4
4x-5x=-8 -1/12x=-7/12
-x=-8 x=-7
x=8

Answer 4

x+2/5=x/4
3/4x=-2/5
x=-8/15

1/4(x+1)=1/3(x-1)
1/4x+1/4=1/3x-1/3
1/12x=7/12
x=7

2x-1/3=x+2/4-1
x=5/6-1
x=-1/6

1/2(x-1)=2-1/5(X+2)
1/2x-1/2=2-1/5x-2/5
7/10x=5/2-2/5
7/10x=21/10
x=3

Answer 5

x+2/5=x/4 x-x/4=-2/5 3x/4=2/5 x=8/15