數學問題唔識做
2008-09-07 1:54 am
a man is 14 years older than his son .Two years later,his age will be twice that of his son .Find the age of his son now.
回答 (4)
2008-09-08 2:15 am
✔ 最佳答案
Let X be the current age of son,and Y be the current age of man.
Now: Y=X+14.......................(1)
2 year later: Y+2=2(X+2)........(2)
Substitute (1) into (2)
(X+14)+2=2(X+2)
X+16=2X+4
16-4=2X-X
so, X=12
2008-09-07 2:36 am
his son is 12 years now
2008-09-07 2:27 am
Let x be the number of the age of his son now
2(x+2)=x+14+2
2x+4=x+16
2x=x+12
x=12
the age of his son is 12 years old now
驗算:
12+2=14
14x2=28
2(x+2)=x+14+2
2x+4=x+16
2x=x+12
x=12
the age of his son is 12 years old now
驗算:
12+2=14
14x2=28
參考: me
收錄日期: 2021-04-25 23:25:01
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080906000051KK02040