问题 解答题
解下列方程.
14
15
-
4
5
+x=1

x+
1
5
+
3
20
=1

4
5
+x=
14
15

x-
1
6
=
1
2
答案

(1)

14
15
-
4
5
+x=1,

2
15
+x=1,

2
15
+x-
2
15
=1-
2
15

x=

13
15

(2)x+

1
5
+
3
20
=1,

x+

7
20
=1,

x+

7
20
-
7
20
=1-
7
20

x=

13
20

(3)

4
5
+x=
14
15

4
5
+x-
4
5
=
14
15
-
4
5

x=

2
15

(4)x-

1
6
=
1
2

x-

1
6
+
1
6
=
1
2
+
1
6

x=

2
3

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