Three and more points are collinear
The answer you're looking for is s=6.
by substitution you'd get 6.
F(x) = 6(9)^x
f(1/2) = 6(9)^(1/2)
f(1/2) = 6(9)^(0.5)
f(1/2) = 6*(9^0.5) 9^0.5 = √9 = +3 or -3.
f(1/2) = 6*3 = 18 or 6*-3 = -18
f(1/2) = 18 or -18
Hope this helps.
Nine million thirty-two thousand five hundred four and seventy-five hundredths