Express cos9x cos3x as a sum of two trigonometry function ​

For a read-a-thon, jay and odhràn each started reading a book at the same time and continued reading for several hours. jay's book had 278 pages, and he read 55 pages per hour. odhràn's book had 238 pages, and he read 45 pages per hour. after how many hours did they have the same number of pages left, and how many pages were left?

Marya wants to factor the polynomial 36x^3 -22x^2 - 144x.which term can she add to the polynomial that would not change its grestest common factor? check all that apply

What is the area of mnp? 40 m2 60 m2 68 m2 127.5 m2