Always compare the exercise numbers from the website with your physical 2009 textbook, as exercises often move in new editions.
Here are the best ways to find reliable, "good paper" (high-quality) solutions for 5th grade 2009 Russian curricula: gdz 5 klass 2009 god
Н.Я. Виленкин (N.Ya. Vilenkin) et al. - This is the most common, reliable choice. Always compare the exercise numbers from the website
Т.А. Ладыженская (T.A. Ladyzhenskaya) et al. gdz 5 klass 2009 god