一條方程式

5/27+x/9 = 2/3
x/9 =18/27-527
x/9 = 13/27
x = (13/27)x9
x = 13/3
x = 4 1/3

5/27 + x/9 = 2/3
5/27 + 3x/27 =18/27
5+3x/27 = 18/27
5+3x-5/27 = 18-5/27
3x/27 =13/27
3x/27x27 = 13/27x27
3x=13
3x/3=13/3
x=13/3

圖片參考：http://imgcld.yimg.com/8/n/HA01052166/o/701008110129513873377360.jpg

希望幫到你啦!!! xd

:5/27+x/9=2/3
x/9=2/3-5/27
x...=9(2/3-5/27)
x....=6-(5/3)
x....=13/3

2010-08-11 18:16:03 補充：
5/27+(13/3)/9

(13/3)/9
(13/3)x(1/9)
13/27
__________
13/27+5/27
=18/27
=2/3

5/27+x/9=2/3

27(5/27+x/9)=2/3(27)
3x=13
x=13/3


2010-08-11 17:42:25 補充：
驗算過啦
真係分數呀