问题 解答题
求未知数X
X
25
=
1.2
75
2X+
3
4
=1
3
4
=
5
6
4x+18=50.
答案

(1)

x
25
=
1.2
75

75x=25×1.2,

75x÷75=25×1.2÷75,

x=0.4;

(2)2X+

3
4
=1,

2X+

3
4
-
3
4
=1-
3
4

2x=

1
4

2x÷2=

1
4
÷2,

x=

1
8

(3)X÷

3
4
=
5
6

3
4
×
3
4
=
5
6
×
3
4

x=

5
8

(4)4x+18=50,

4x+18-18=50-18,

4x=32,

4x÷4=32÷4,

x=8.

单项选择题
单项选择题