问题 解答题
解方程
x+
1
5
=
7
4
x-
3
4
=
9
4
x+(
4
5
+
1
3
)=
2
3
答案

(1)x+

1
5
=
7
4

x+

1
5
-
1
5
=
7
4
-
1
5

x=1

11
20

(2)x-

3
4
=
9
4

x-

3
4
+
3
4
=
9
4
+
3
4

x=3;

(3)x+(

4
5
+
1
3
)=
2
3

x+

17
15
=
2
3

x+

17
15
-
17
15
=
2
3
-
17
15

x=-

7
15

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