Answer:
adult tickets and
child tickets were sold.
Explanation:
Let
represents the number of adult tickets sold and
represents the number of child tickets.
The total number of tickets sold was
. So we can write the equation,

Adult tickets were sold at $
each. This means that,
number of adult tickets will yield $
.
Child tickets were sold at $
each. This means that,
number of adult tickets will yield $
.
The total amount collected was $
.
We can write this equation for the total amount collected.

Let us make
the subject in equation (1) to get,

We put equation (3) in to equation (2) to get,

We expand the brackets to get,

We group like terms to get,


We divide both sides by
to get,

This implies that,

We substitute
into equation (3) to get,


Hence
adult tickets and
child tickets were sold.