1. (x-3) (x+2) = -9
2. x(2x+7) = 3(2x+7)
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2008-09-16 3:57 am
回答 (2)
2008-09-16 4:10 am
2. x(2x+7)=3(2x+7)
x(2x+7)/(2x+7)=3
x=3
x(2x+7)/(2x+7)=3
x=3
2008-09-16 4:07 am
1. (x-3) (x+2) = -9
x^2-x-6=-9
x^2-x+3=0
(x-3)(x+2)=0
2. x(2x+7) = 3(2x+7)
2x^2+7x=6x+21
2x^2+x-21=0
(2x+7)(x-3)=0
x^2-x-6=-9
x^2-x+3=0
(x-3)(x+2)=0
2. x(2x+7) = 3(2x+7)
2x^2+7x=6x+21
2x^2+x-21=0
(2x+7)(x-3)=0
參考: me
收錄日期: 2021-04-15 01:24:00
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080915000051KK02464