中4數學(二次方程)
回答 (1)
2010-10-25 10:25 am
✔ 最佳答案
因為男人同個女年齡差距係年年都唔變既所以男人同女今年既差距 = 以前既差距
今年既差距 = [(x+1)^2] - (2x+11)
以前既差距 = 5x - 4
(x+1)^2 - (2x+11) = 5x-4
x^2 + 2x +1 -2x -11 = 5x-4
x^2 - 5x -6 = 0
(x-6)(x+1) = 0
x = 6 or x = -1 (reject) 英文係寫reject 唔知中文寫咩
(reject原因:
( [(-1)+1]^2 = 0歲
男人今年的年齡
= (6+1) ^2
= 49
數就咁計既
但係我唔知點解唔合理 = ="
收錄日期: 2021-04-13 17:36:01
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20101025000051KK00067