Answer: No. The assistant is wrong as 334 tickets were sold at the door and 409 tickets were sold before the tournament.
Step-by-step explanation:
To know if the number of tickets sold at the door and before the tournament as stated by the assistant is correct, we've to solve the equation given.
x + y = 743 ......... i
x – y = 75 ........... ii
Add the equations together
2x = 818
Divide both side by 2
2x/2 = 818/2
x = 409
Since x + y = 743
Therefore, 409 + y = 743
y = 743 - 409
y = 334
Therefore, 334 tickets were sold at the door and 409 tickets were sold before the tournament.
Therefore, the assistant is wrong as 334 tickets were sold at the door and 409 tickets were sold before the tournament.