One such a value of "a" comes from the equation 5a - 4 = a 5a - a = 4 4a = 4 a = 4/4 = 1. Other such a value of "a" comes from the equation 5a - 4 = -a 5a + a = 4 6a = 4 a = = . The product of these values, 1 and , is . ANSWER