Tickets for a show cost 3 dollars or 5 dollars. If 50 tickets were sold for a total of 230 dollars, how many tickets were sold for 3 dollars

x = number of 3 dollar tickets, y = number of 5 dollar tickets

3x + 5y = 230

x + y = 50 so y = 50 - x.  Put this in the first equation:

 

3x +5(50 - x) = 230

3x +250 -5x = 230

-2x = -20

x = 10

y = 50 - 10

y = 40

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