1條中一數學題.幫幫手吧!

2008-01-05 5:12 am

唔該去呢個網睇,
http://img146.imageshack.us/img146/250/by2ep1.png

呢條數學題我諗諗去都唔識,
請教下我!有幾詳細得幾詳細!愈詳細愈好!

回答 (4)

2008-01-05 5:34 am

✔ 最佳答案

正方形周界=7X4=28cm
長方形周界=2(長+闊)=2[(2x-6)+1/2x]
因為長方形ABCD跟正方形PQRS相同,

2[(2x-6)+1/2x]=28
[(2x-6)+1/2x]=14
2x+1/2x-6=14
5/2x=20
x=20X2/5
x=8

因此x=8.

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2008-01-06 5:09 am

(2x-6)+(2x-6)+(1/2x)+(1/2x)=7*4
4x-12+x=28
5x-12=28
5x=28+12
5x=40
x=8

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2008-01-05 11:49 pm

2.5x-6=14
2.5x=14+6
2.5x=20
x=8

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2008-01-05 5:18 am

答案係咁...

(2x-6+(1/2)x)*2=7*4

(2x-6+0.5x)*2=28

(2.5x-6)*2=28

2.5x-6=14

2.5x=20

x=8

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