Which exponential function has a growth factor of one-half? f(x) = 2(0.5x) on a coordinate plane, an exponential function decreases from quadrant 2 into quadrant 1 and approaches y = 0. it goes through (negative 1, 2) and crosses the y-axis at (0, 0.5). f(x) = 0.5(2x) a 2-column table has 5 rows. the first column is labeled x with entries negative 2, negative 1, 0, 1, 2. the second column is labeled f (x) with entries one-eighth, one-fourth, one-half, 1, 2.