Answer:
The total cost of ordering 4 tickets is $43.
Explanation:
Let 
 = number of tickets
 = number of tickets
The given expression to find total cost to order:

To find the total cost of ordering 4 tickets, simply substitute 4 for 
 in the expression, and solve:
 in the expression, and solve:


Therefore, the total cost of ordering 4 tickets is $43.
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You can check your work by setting the given expression equal to 43:

Subtract 
 from both sides of the equation:
 from both sides of the equation:

Divide both sides of the equation by the coefficient of 
 , which is
, which is 
 :
:

This shows that the cost of ordering 4 tickets is in fact, $43.
Our solution is correct!