Question 1164874
The first is exponential with f(x)=4.5*2^x

look at when x=0. Then a must be 4.5
9 is 4.5 *2 and 18 is 4.5*4 and (1/2) and (1/4) for the negative values of x

for the second, ab^x=3 when x=0 so a=3
when x=1 3b^1=1.5 so b=(1/2)
when x=-1 3b^1=3*2 or 6, flipping the fraction with a negative exponent (1/2)^-1 is 2
it is exponential and 3*0.5^x=f(x)