Elaina and her brother each have coin collections. One year, they decided to increase the number of coins in each of their collections by a certain amount each year. When Elaina began adding to her collection, she had 14 coins and committed to buying 3 more each year. The number of coins in her brother's
collection could be modeled by the equation 9 (a) = 42 + 11, in which 9 (a) is the number of coins and a is the number of years since they both started
adding to their collections. Which statement is true regarding the number of coins the siblings have in their collections?