1. 1/5=2x-1/21
2. 8/a=16
3. 1/3(4x-3)=1
4. 6/a -4.4=0.4
方程式一問 7(詳列步驟)
2009-08-27 4:13 am
回答 (3)
2009-08-27 4:24 am
✔ 最佳答案
1)1/5=2x-1/211/5+1/21=2x
26/105=2x
x=13/105
2)8/a=16
a=8/16
a=0.5
3)1/3(4x-3)=1
4x-3=1除以1/3
4x-3=1X3/1
4x-3=3
4x=6
x=1.5
4) 6/a -4.4=0.4
6/a=4.8
a=6/4.8
a=1.25
參考: me
2009-08-27 4:27 am
( 1 )
1/5 = 2x -1/21
1 = ( 2x -1/21 ) X5
1 = 10x -5/21
( 1 -10x ) X21 = -5
21 -210x = -5
-210x = -5 -21
-210x = -26
x = 26/210
x= 13/105
( 2 )
8/a = 16
8 = 16a
8/16 = a
a = 0.5
( 3 )
1/3( 4x -3 ) = 1
4x -3 = 3
4x = 6
x = 6/4
x = 1.5
( 4 )
6/a -4.4 = 0.4
6/a = 0.4 +4.4
6/a = 4.8
6 = 4.8a
6/4.8 = a
a = 1.25
hope can help you~
1/5 = 2x -1/21
1 = ( 2x -1/21 ) X5
1 = 10x -5/21
( 1 -10x ) X21 = -5
21 -210x = -5
-210x = -5 -21
-210x = -26
x = 26/210
x= 13/105
( 2 )
8/a = 16
8 = 16a
8/16 = a
a = 0.5
( 3 )
1/3( 4x -3 ) = 1
4x -3 = 3
4x = 6
x = 6/4
x = 1.5
( 4 )
6/a -4.4 = 0.4
6/a = 0.4 +4.4
6/a = 4.8
6 = 4.8a
6/4.8 = a
a = 1.25
hope can help you~
參考: 自己
2009-08-27 4:21 am
1)1X21=5(2x-1)
21=10x-5
10x=26
x=26/10
2) 16a=8
a=8/16
a=2
3) 4x-3=1X3
4x=3+3
x=3/2
4) 6/a=0.4+4.4
6=4.8a
a=5/4
21=10x-5
10x=26
x=26/10
2) 16a=8
a=8/16
a=2
3) 4x-3=1X3
4x=3+3
x=3/2
4) 6/a=0.4+4.4
6=4.8a
a=5/4
收錄日期: 2021-04-13 16:48:47
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https://hk.answers.yahoo.com/question/index?qid=20090826000051KK02130