The exponential function has the following form:
[tex]y=a\cdot b^x[/tex]The function goes through the points ( 0, 19) and ( 2, 171 )
We will use the points to find the values of a and b
[tex]\begin{gathered} x=0\rightarrow y=19 \\ \\ 19=a\cdot b^0 \\ b^0=1 \\ a=19 \end{gathered}[/tex]Substitute with the point ( 2, 171 ) and the value of a to find b
[tex]\begin{gathered} x=2\rightarrow y=171 \\ a=19 \\ \\ 171=19\cdot b^2 \\ \\ b^2=\frac{171}{19}=9 \\ \\ b=\sqrt[]{9}=3 \end{gathered}[/tex]So, the answer will be:
[tex]y=19\cdot3^x[/tex]