To model the scenario with a two-variable equation, we know the following:
- The cost of an adult ticket is $9.
- The cost of a child ticket is $6.75.
- The total sales for one movie showing is $1406.25.
Let:
- \( a \) = number of adult tickets sold
- \( c \) = number of child tickets sold
The sales from adult tickets can be expressed as \( 9a \) and the sales from child tickets can be expressed as \( 6.75c \).
To represent the total ticket sales, the equation would be:
\[ 9a + 6.75c = 1406.25 \]
Thus, if we fill in the blank represented by "_": 9a + 6.75c = 1406.25
So, in this case, the "_" represents the sales from child tickets, which is \( 6.75c \).