Answer:
[tex]given \: that \: the \: cost \: of \: orchestra \: is \: three \: times \: of \: balcony \: ticket \\  let \: the \:cost \: of \:  balcony \: \: ticket \:  be \:x \\ so \: the \: cost \: of \: orchestra \: ticket \: sold \: be \: 3x \\ the \: total \: income = 3640 \\  \\ so \: the \: equation \: formed \:  = > 148(3x)+ 76(x) = 3640 \\  =  > 444x + 76x = 3640 \\  =  > 520x = 3640 \\  =  > x =  \frac{3640}{520} \\  =  > x = 7[/tex]
[tex]so \: orchestra \: ticket \:  = 444x = 444 \times  = 3108 \\ and \: balcony \: ticket \:  = 76x = 76 \times 7 = 532[/tex]
FOR PROOF = 3108+532 = 3640 total income 
Hope it helps