The expression 5a + 3c can be used to find the cost of a adults and c children to attend the school play, so we have a expression as a function of the number of adults a and the number of children c. Therefore:
[tex]C(a,c)=5a+3c[/tex]What is the cost of 4 adults and 9 children to attend the school play?
[tex]\begin{gathered} a=4 \\ c=9 \\ C(4,9)=5(4)+3(9) \\ C(4,9)=20+27 \\ C(4,9)=47 \end{gathered}[/tex]$47
