8 is called 
              a square root of 64 because 8 x 8 = 64. But -8 is also a square 
              root of 64 as -8 x -8 = 64.
			  
			  
			  Every positive number has two square roots, 
              one positive and one negative.
              841 let say has 29 and -29 as its square roots because 29 
              x 29 = 841 and -29 x -29 = 841.
			  
              In general m is called a square root of a number N if m x m = N, 
              and then it will always be true that -m is also a square root.
			  
			  
			  The Notation √N 
				can be used for the positive square root of a number. 
              Note that the positive square root of a number between 0 and 1 is 
              always bigger than that number. √0.1681,
			  for example, equals 0.41 
              which is bigger than 0.1681.