Winchester store charges $19 per charm, so if she uses 3 charms, the cost is 19*3, if she uses 5, the cost is 19*5, if she uses "c" charms, the cost of that will be 19*c or 19c. They also charge a fixed value of 47 bucks for the bracelet to put it on.
Winchester charges in total then 19c + 47
Kim store charges $18 for the charms, so if she uses 3 charms, that'd be 18*3, if she uses 7 charms, that'd be 18*7, if she uses "c" charms, that'd be 18c. They also charge 48 bucks for the bracelet.
Kim charges in total then 18c + 48.
if the costs "equal" each other, then
[tex]\bf \begin{cases}
19c+47\\
18c+48
\end{cases}\implies 19c+47=18c+48\implies c=1\\\\
-------------------------------\\\\
\stackrel{\textit{total cost at Winchester}}{19(1)+47}=\stackrel{\textit{total cost at Kim}}{18(1)+48}[/tex]