The number of flights departing daily from an airport in 198

The number of flights departing daily from an airport in 1988 was 59. In 2010, there were 220 departing flights per day. Let y be the number of fllights departing daily from the airport in the year x, where x=0 represents the year 1988.

a.) Write a linear equation in the slope-intercept form that models the increase in the number of daily departing flights in terms of x. [Hint:the line must pass through the points (0, 59) and (2, 220) ].

b.)Use this equation to predict the number of daily departing flights in the year 2018.

c.) Explain what the slope for this line means in the context of the problem.

Solution

in 1988 i.e x = 0 , number of flights departing y = 59

in 2010 i.e x = 22, y = 220

so equation of straight line passing throught points (0, 59) and (22, 220) is

(y- 59) = {(220-59)/(22-0)}(x-0)

=> y-59 = 7.31818181818 x

=> y = 7.31818181818x +59 ----------------------------answer(a)

so for year 2018 , x= 30 and hence

y = 7.31818181818 * 30 +59

= 278.545454545

approx 278 ------------------------------answer(b)

answer(c) slope means number of increase in flights per year