Hi,
P =0r **** L + w = 21m
the length of a rectangle is 5 meters more than the width
(x+5m) + x = 21m
2x + 5m = 21m
2x = 16m
x = 8m, the width and the length is 13m
CHECKING our answer***
21m + 8m = =21m 0r 26m+ 16m = 42m
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