[tex] cost \: of \: 1 \:bracelet \\(no\:shipping): \\72 \: dollars - 9 \: dollars \: shipping = \\ 63 \: \div 9 \: = cost \: of \: 1 \: bracelet \: \\ = 7 \: dollars [/tex]
[tex]\\cost \: of \: shipping: \\ 9 \: dollars \: \div 9 \: bracelets \: = \\ 1 \: dollar\: per\:bracelet \\ \\ formula \: for \: cost \: overall: \\ 7y \: + y [/tex]
y = quantity, for example:
I want to buy 1 bracelet =
1×7 = 7 + 1 = 8$ per bracelet