4x^2-84x+476
點解到x=3 或 x=18呀??
解以下既方程~~~急
2006-10-15 8:09 pm
回答 (4)
2006-10-15 8:27 pm
你比錯式........
2006-10-15 12:28:46 補充：
係216唔係276
2006-10-15 12:28:46 補充：
係216唔係276
2006-10-15 8:16 pm
4x^2-84x+216=0
4(x^2-21x+54)=0
x^2-21x+54=0
(x-3)(x-18)=0
x-3=0
x=3
Or
x-18=0
x=18
So, x=3 or x=18.
4(x^2-21x+54)=0
x^2-21x+54=0
(x-3)(x-18)=0
x-3=0
x=3
Or
x-18=0
x=18
So, x=3 or x=18.
參考: me
2006-10-15 8:16 pm
4x^2-84x+476
= 4(x^2-21x+119)
最多去到咁
= 4(x^2-21x+119)
最多去到咁
收錄日期: 2021-04-13 16:10:27
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061015000051KK01828