What variable for both sides is 4a-4=8+a

Rachel reads 1/5 of the pages of a book plus 12 pages on the first day. on the second day, she reads 1/4 of the remaining pages plus 15 pages. on the third day, she reads 1/3 of the remaining pages plus 18 pages. on the fourth day, she reads the remaining 70 pages. how many total pages are in the book?

Is δ pmr similar to δ smn ? if so, which postulate or theorem proves these two triangles are similar?

If the class was going to get a class pet and 5 picked fish and 7 pick bird and 8 picked rabbits have many students were in the