Solve each equation for x, giving both an exact value and a decimal approximation: log3(x² - x - 6)

a) x = -2, x = 3; Decimal Approximation: x = -2, x = 3
b) x = -3, x = 2; Decimal Approximation: x = -3, x = 2
c) x = -3, x = 3; Decimal Approximation: x = -3, x = 3
d) x = -2, x = 2; Decimal Approximation: x = -2, x = 2