the width of a rectangle is 7 cm shorter than the length .if the perimeter of the rectangle is 38 cm

题目

the width of a rectangle is 7 cm shorter than the length .if the perimeter of the rectangle is 38 cm ,find
(a) the width
(b) the length
(c) the area of the rectangle

答案

题意：一个矩形的宽度比长度短了7厘米.如果矩形的周长是38厘米,得到(a)宽度　(b)长度(c)矩形区域设length长=x,则width宽=x-7perimeter周长=2（x+x-7）=38.解之,得x=13the width宽=the length长-7=13-7=6(b) 由（a）...