we have, |f-6| = |f+8| we will get two equations, f-6 = f+8, which cannot be true Here, f cannot be a real no. f-6 = -(f+8) --- (2) => f-6=-f-8 => 2f = -2 => f = -1 Since the equation 1 cannot be true it is rejected, we take the value of f from the equation 2 Hence the value of f is -1