We know: The total number of tickets is 35. Another way of saying this is the number of adults plus the number of children equals 35. i.e.:

Using the symbols provided we can write this is as:

We also know: The total money collected is $75. We know that $6 was collected for every adult or

and $1 for every child or

. i.e.:

Using the symbols provided and adding it all up we can write this is as:

Equation 1:

Equation 2:
Opposite sides of a rectangle are congruent
QT = RS
45 = 5x - 5
50 = 5x
10 = x
D is the answer
The answer is in the photo