Answer: There are 475 balcony seats.
Step-by-step explanation:
Let be "b" the number of balcony seats in the theater and "o" the number of ochrestra seats in the theater.
Set up a system of equations:
[tex]\left \{ {{b+o=1200} \atop {b=o-250}} \right.[/tex]
Applying the Subsitution method, you can solve for "o" from the first equation:
[tex]o=1200-b[/tex]
Now substitute this into the second one and solve for "b", in order to find its value:
[tex]b=(1200-b)-250\\\\2b=950\\\\b=\frac{950}{2}\\\\b=475[/tex]
