The piece of land is x m long and y m wide. Earlier, we are given that the piece of land is rectangular.

So, area of the land
= x times y
= xy m²

and perimeter of the land
= x + y + x + y
= (2x + 2y) m

Since the area of the land is 216 m²,
xy = 216 --> we call this equation 1

Since the enclosure of fencing is 60 m long,
2x + 2y = 60
x + y = 30
y = 30 - x --> we call this equation 2

If we substitute equation 2 into equation 1,
x (30 - x) = 216
30x - x² = 216
0 = x² - 30x + 216
x² - 30x + 216 = 0
(x - 12) (x - 18) = 0 --> cross factorisation
x - 12 = 0 or x - 18 = 0
x = 12 or x = 18

Substituting each value of x into equation 2,
y = 30 - 12 or y = 30 - 18
y = 18 or y = 12

So, the piece of land measures 18 m by 12 m long.