Ezra and tara sold at least 150 coupon books. ezra sold at most 30 books more than twice the number tavares sold. show and describe all possible combinations of the numbers of coupon books ezra and tavares sold. list teo possible combinations.

The answers are (110,40), (120,45), (130,50), etc.

Step-by-step explanation: Given that Ezra and Tara sold at least 150 coupon books and Ezra sold at most 30 books more than twice the number Tavares sold. We are to list the possible combinations of the numbers of coupon books Ezra and Tavares sold.

Let, 'x' and 'y' be the number of coupon books sold by Ezra and Tavares respectively. Then according to the question, we have

Writing these inequalities as equations, we have

Multiplying the first equation by 2 and adding to the second equation, we have

So,

Thus, the possible combinations are

(110,40), (120,45), (130,50),etc.

answer: cos [   arcsin (3/5) - arccos (1/2) ] =

step-by-step explanation: × = 3/5 = 0.6--> x = 36.87 and x = 180 - 36.87 = 143.13 deg

cos y = 1/2 --> y = +- 60 deg a. cos (x - y) = cos (143.13 - 60) = cos 83,13  

=

0.12

b. cos (36.87 - 60) = cos (-23.23) = 0.92