A bookstore sells textbooks for $120 each and notebooks for $6 each. The bookstore would like to sell $1,080 in merchandise by the end of the week. Graph the linear equation 120t + 6n = 1080, where t is the number of textbooks sold, and n is the number of notebooks sold.

anyone? find the second, fifth, and ninth terms of a sequence where the first term is 65 and the common difference is -7. 72, 93, 121 72, 79, 86 58, 37, 9 58, 51, 44

Mozart lenses inc. recently introduced seelites, a thinner lens for eyelasses. of a sample of 800 eyeglass wearers, 246 said they would purchases their next pair of eyeglasses with the new lenses. lenses inc. estimates that the number of people who purchase eyeglasses in a year is 1,700,000. most eyeglasses wearer buy one new pair of eyeglasses a year. what is the annual sales potential for the new lenses.

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .