350 tickets sold of children and 425 tickets sold for adult.
Algebra is a branch of mathematics dealing with symbols and the rules for manipulating those symbols.
Let x be the number of adult tickets that were sold and y be the number of children's tickets that were sold.
Total 775 tickets were sold for the game.
So,
x + y = 775
If adults tickets sold for 2.50 and children's tickets sold for 1.50 and all the tickets were sold for a total of 1587.5, it means that
2.5x + 1.5y = 1587.5
put x = 775 - y
2.5(775 - y) + 1.5y = 1587.5
1937.5 - 2.5y + 1.5y = 1587.5
-y = 1587.5- 1937.5
y = 350
and, x = 775 - y = 775 - 350
x = 425
Learn more about this concept here:
https://brainly.com/question/15371020
#SPJ1