1 2 x+2.5=4 3 5 . 2 3 (x-1 1 4 )=1.8 3x+7 7 10 x=5..

1 2 x+2.5=4 3 5 . 2 3 (x-1 1 4 )=1.8 3x+7 7 10 x=5 7 20 .
2025-06-23 01:45:49
推荐回答(1个)
回答1:


(1)
1
2
x+2.5=4
3
5

1
2
x+2.5-2.5=4
3
5
-2.5

1
2
x=2.1,
1
2
1
2
=2.1÷
1
2

x=4.2;

(2)
2
3
(x-1
1
4
)=1.8

2
3
(x-1
1
4
2
3
=1.8÷
2
3

x-1
1
4
=2.7,
x-1
1
4
+1
1
4
=2.7+1
1
4

x=3.95;

(3) 3x+7
7
10
x=5
7
20

10
7
10
x=5
7
20

10
7
10
x÷10
7
10
=5
7
20
÷10
7
10

x=
1
2