A theater charges $7.50 for adults and $4 for children. Write a numeric expression that shows the total cost of
buying 4 adult tickets and 3 children's tickets.

The party planning committee has to determine the number of tables needed for an upcoming event. if a square table can fit 8 people and a round table can fit 6 people, the equation 150 = 8x + 6y represents the number of each type of table needed for 150 people.