Answers

2015-01-18T09:32:53+08:00
The width is 31
The length is 21

the missing is the width
             
                 52
              -  10       --- subtract the feet longer first in the perimeter
              ----------
                 42

Then divide 42 ÷ 2 = 21 
21+ 10 = 31
the answer is 31
                    
1 5 1
Excuse me, it says that 52 is the perimeter, Perimeter= L+W+L+W 31+21=52
yes its short cut
2015-01-18T10:34:24+08:00
Let x = the width
let x + 10 = the length

P = 2L + 2W

52 = 2(x+10) + 2x
52 = 2x + 20 + 2x
52 = 4x + 20
52-20=4x
32=4x
1/4(32) = (4x)1/4
8 = x

..therefore, width = x = 8ft
length = x +10 = 8+10 = 18ft

dimension : 18 by 8
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