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7u-﹝(4u-1)/2﹞=21

14u - 4u + 1 = 42
10u = 41
u = 4.1

14u - 4u + 1 = 42
10u = 41
u = 4.1

7u - ((4u-1)/2) = 21
7u - 21 = (4u-1)/2
(7u - 21) x 2 = 4u - 1
14u - 42 = 4u - 1
14u - 4u = -1 + 42
10u = 41
u = 41/10
u = 4.1

　　　4u - 1
7u - ──── = 21
　　　　2
　14u - (4u-1) = 42
　　　10u+1 = 42
　　　　10u = 41
　　　　　u = 4.1

7u-﹝(4u-1)/2﹞=21
2* {7u-﹝(4u-1)/2﹞} = 21*2
14u - (4u-1) = 42
14u - 4u + 1 = 42
10u = 42 - 1
10u = 41
u = 4.1

7u-[(4u/2-1/2]=21
7u-2u+1/2=21
5u=20.5
u=20.5/5
u=4.1

解:7u-﹝(4u-1)/2﹞=21
7u-(4u-1)=10.5
7u-4u+1=10.5
3u=9.5
u=95/30

2006-10-24 22:17:03 補充：
````````````````````````````````````````````以下的才對7u-﹝(4u-1)/2﹞=21 14u-(4u-1)=4214u-4u+1=4210u=41u=4.1

7u-﹝(4u-1)/2﹞=21
7u -21 = (4u-1)/2
2(7u-21) = 4u-1
14u-42 = 4u-1
14u-4u=42-1
10u=41
u =4.1

-[(4u-1)/2] = 21-7u
4u-1=14u-42
10u=41
u=4.1