For the years from 2001-2010, the number of americans traveling to other countries by plane
can be represented by the polynomial function a(t) = 20t^4 – 428t^3 + 2760t^2 – 4320t + 33,600,
where a is the number of thousands of americans traveling abroad
by airplane and t is the number of years since 2001. in which year
were there 40,000,000 americans traveling abroad? use the
rational root theorem to find your answer.
(hint: consider the function's domain and range before finding all
possible rational roots.)

is should be y = 5x

step-by-step explanation:

correct me if im wrong

proportions are fractions that equal to each other. so if two fractions are the same, they are proportional.

let's check the answers to see if they are proportional.

question a is not proportional because you can't turn 1.5/3 to 3/9. if you try to multiply 1.5/3 by 2 or 3, you wont get 3/9. it's impossible to make the fractions the same.

question b is not proportional because you can't turn 22/33 to 4/6. 33 can't go into 6.

question c is proportional because when you multiply 2 and 3 by 71, you would get 142/213, and those fractions equal to each other

question d is proportional because when you divide 14 and 7 by 2, you would end up with 7/3.5, and those fractions equal to each other.