suppose length is X -----> [1]
so the width is X - 5 -----> [2]
perimeter of rectangle = 2 ( length + width )
50 = 2 ( X + X - 5 )
50 = 2 ( 2X - 5 )
50 = 4X - 10
50 + 10 = 4X
60 = 4X
60/4 = X
15 = X
subsitute in [1] and [2]
length = 15 meters
width = 15 - 5 = 10 meters