if the perimeter of a rectangle is at most 16cm and the difference between the length and the width of the rectangle is 2cm,find
(a)the maximum width of the rectangle:
(b)the maimum area of the rectangle.
maths!
2007-08-30 8:47 am
回答 (1)
2007-08-30 8:53 am
✔ 最佳答案
Let the width be xcm and so the length is ( x + 2 )cm. a) 2 { x + ( x + 2 ) } ≦ 16 { As at most the perimeter is 16cm }
x + x + 2 ≦ 8
2x ≦ 6
x ≦ 3
Hence the maximum width is 3cm.
b) Then the maximum length: ( 3 + 2 ) cm = 5cm
Hence the max. area: 3 x 5 = 15cm^2
參考: My Maths Knowledge
收錄日期: 2021-04-23 20:34:02
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070830000051KK00239