问题 解答题
解方程
4
5
+x=
14
15
x-
1
6
=
1
2
x-0.25=
2
5
x-
2
3
+
2
7
=
2
7
答案

(1)

4
5
+x=
14
15

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

x=

2
15

(2)x-

1
6
=
1
2

x-

1
6
+
1
6
=
1
2
+
1
6

x=

2
3

(3)x-0.25=

2
5

x-0.25+0.25=0.4+0.25,

x=0.65;

(4)x-

2
3
+
2
7
=
2
7

x-

2
3
+
2
7
-
2
7
=
2
7
-
2
7

x-

2
3
=0,

x=

2
3

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