The book edited by F.F. Lysenko and S.Y. Kulabukhova is a well-known training manual designed to help 9th-grade students in Russia master the State Final Examination (GIA).
Instead of a dry list of answers, here is a story of a student named Alex who used this exact manual to conquer his math fears. The Midnight Variable
Walking into the classroom, Alex felt a strange sense of calm. When he opened the exam booklet, he saw a problem almost identical to one he had solved in the blue manual. He smiled, picked up his pen, and began to write.
The blue and white cover of the manual stared back at Alex like an unsolved mystery. It was two weeks before the GIA-2013, and the geometry section felt like a foreign language. Alex opened the book to the first practice test, his pencil hovering over a problem about inscribed circles.