Todd has a collection of 8 cds and sally has a collection of 18 cds. todd is adding 9 cds a month to his collection while sally is adding 7 cds a month to her collection. when will they have the same number of cds and how many cds will they have?

15. jiovanni is looking in to two different companies that offer study guides for math exams.test prep 101 charges a $5 flat fee and an additional $0.25 per problem.math charges a $2 flat fee and an additional $0.50 per problem.how many prablems would make the costs of the two companies be equal? varibles: equations/eniqualities{ {