Erica purchased adult and youth tickets for a movie. she bought x adult tickets for $7 each and y youth tickets for $5. write an expression that can be used to show the total cost, c, of all tickets.
a. c = 7x + 5y
b. c = (7 + 5)x
c. c = (7 + 5)(x + y)
d. c = 7y + 5x

 A  

Step-by-step explanation: I got my answer from peesneez and I also got a 100 on the test so, Thanks Peesneez!

graph b

step-by-step explanation:

one solution- graph a (clear intercepting point.)

no solution- graph b (they're parallel, there will never be a point of interception.)

infinite solutions- graph c (all points intercept.)

ok thats very interesting