解方程.5x-0.4=2.4

解方程.5x-0.4=2.4 1-227x=1934x-25x=710.
2024-11-05 21:51:02
推荐回答(1个)
回答(1):

(1)5x-0.4=2.4
    5x-0.4+0.4=2.4+0.4
            5x=2.8
         5x÷5=2.8÷5
             x=0.56;

(2)1-

2
27
x=
1
9

1-
2
27
x
+
2
27
x=
1
9
+
2
27
x
      
2
27
x=1
 
2
27
x+
1
9
-
1
9
=1-
1
9

      
2
27
x=
8
9

  
2
27
2
27
=
8
9
÷
2
27

          x=12;

(3)
3
4
x-
2
5
x=
7
10

      
7
20
x=
7
10

  
7
20
7
20
=
7
10
÷
7
20

          x=2.