The Solution.
The given sequence is
[tex]5,14,23[/tex]The common difference of the arithmetic sequence is given by the formula below:
[tex]\text{common difference(d)=T}_2-T_1=T_3-T_2[/tex]In this case,
[tex]T_1=5,T_2=14,T_3=23[/tex]Substituting these values in the formula above, we get
[tex]\begin{gathered} \text{common difference = 14-5=23-14}=9 \\ \text{common difference}=9 \end{gathered}[/tex]So,the correct answer is 9.