Answer:
A. it depends on the number of friends who will watch the movie
B. If there are 2 friends the cost of each cinema are exactly same
C. Substitution and elimination method
Explanation:
Let y = the total cost of the cinema + 3 tubs of popcorn
let x = the number of friends
Theater A
y = 14.50x + 3(5.75)
y = 14.50x + 17.25 Equation1
Theater B
y = 13x + 3(6.75)
y = 13x + 20.25 Equation2
substitute Equation1 to Equation2
14.50x + 17.25 = 13x + 20.25
14.50x - 13x = 20.25 - 17.25
1.5x = 3
x = 2
it means that the cost of the cinema + 3 tubs of popcorn are the same if there are 2 friends who will watch the movie