Explanation
To convert 5 ft and 9 inches into inches we will convert the feet part to inches and sum it with the part that is already in inches
The next step would be to multiply the length value of the feet by 12, as this would convert it to inches.
[tex]\begin{gathered} 5ft\Rightarrow5\times12\Rightarrow60inches \\ therefore \\ 5ft\text{ and 9 inches}=60inches+9inches=69inches \end{gathered}[/tex]Answer: 69 inches