數學題.........
1. 2 / 3 ( a - 2 ) = 6
2. 1 / 5 ( 2 a - 3 ) = 3
回答 (15)
✔ 最佳答案
1. 2 / 3 ( a - 2 ) = 6
a - 2 = 9
a = 11
2.1 / 5 ( 2 a - 3 ) = 3
2 a - 3 = 15
2a = 18
a = 9
Q 1. 2 / 3 ( a - 2 ) = 6
3/2*2 / 3 ( a - 2 ) = 6*3/2
a - 2= 9
a = 9+2
∴ a=11
Q 2. 1 / 5 ( 2 a - 3 ) = 3
5/1*1 / 5 ( 2 a - 3 ) = 3*5/1
2 a - 3 =15
2a=15+3
a= 18/2
∴=9
2006-10-21 19:15:08 補充:
SORRY~~應該係除去咗1/5唔係5/1
參考: Q1同Q2 我都用咗抵消法, 分別除去咗2/3同5/1, 減少幾個計算嘅Steps
以下題目(除)以#代表
1.
2/3(a-2)=6
(a-2)=6#2/3
(a-2)=6x3/2
(a-2)=9
a=9+2
a=11
2.
1/5(2a-3)=3
(2a-3)=3#1/5
(2a-3)=3*5/1
(2a-3)=15
2a=15+3
2a=18
a=18/2
a=9
2006-10-21 18:55:59 補充:
點解x變左除,加變減係因為用左消除法
1.
2/(3a-6)=6
3a-6=1/3
3a=19/3
a=19/9
2.
10a-15=1/3
10a=46/3
a=46/30
1.a=(12 2/3)/6
2.a=9
*(12 2/3)=12又2/3
參考: 自己計
1. 2/3(a-2)=6
a-2=9
a=9+2
a=11
2. 1/5(2a-3)=3
2a-3=15
2a=15+3
2a=18
a=18/2
a=9
1.2/3(a-2)=6
a-2=6÷2/3
a=9+2
a=11
2.1/5(2a-3)=3
2a-3=3÷1/5
2a=15+3
a=18÷2
a=9
希望幫到你la......
收錄日期: 2021-04-12 22:58:37
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