2 x 2 or 2 + 2 = 5 We Know That, - 20 = - 20 or, 16 - 36 = 25 - 45 or, 16 - 36 + 81/4 = 25 - 45 + 81/4 or, 42 - 2 x 4 x 9/2 + (9/2)2 = 52 - 2 x 5 x 9/2 + (9/2)2 or, ( 4 - 9/2)2 = (5 - 9/2)2 or, √(4 - 9/2)2