Start by writing the equation for the total cost of the greeting cards, if x is the number of small greeting cards multiplied by its costs, the same will happen for the large greeting cards
[tex]C=2.15x+5.40y[/tex]then using the equation replace x for 2 and y for 5
[tex]\begin{gathered} C=2.15(2)+5.40(5) \\ C=31.3 \end{gathered}[/tex]