Let the length of rectangular yard be x m and the width of rectangular yard be y m.
According to the question, we have:
2(x + y) = 60
⇒ x + y = 30 ...(1)
and
x = y + 6
⇒ x y = 6 ...(2)
Adding (1) and (2), we get:
x + y = 30
x y = 6
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2x = 36
⇒ x = 18
Substituting the value of x in equation (1), we get:
18 + y = 30
⇒ y = 12
∴ Length = 18 m and width = 12 m