getter+setters "Properties problem"

Question

i got to write a console application..that prints out a square. Class square should contain two constructors and an instance property Side that has get and set accessors for private data. The first constructor is a default constructor that takes no arguments and another takes a side length as a value. I got to write a test application to test the square fuctions that i define.. Please help as i dont have any idea as how to solve this problem.. thanks in advance..