In 1990, the life expectancy of males in a certain country was 69.9 years. In 1995, it was 72.8 years.
Let E represent the number of years since 1990

E(t)= _ t+ _ ????
(round to the nearest tenth)

Use the function to predict the life expectancy of males in 2006
E(16)= ??

Question

In 1990, the life expectancy of males in a certain country was 69.9 years. In 1995, it was 72.8 years. 
  Let E represent the number of years since 1990

E(t)= _ t+ _    ????
(round to the nearest tenth)

Use the function to predict the life expectancy of males in 2006
    E(16)= ??

anonymous · Answer

I know there were 5 years since 1990 to 1995, and I know that there is 16 years between 1990 and 2006, I just do not know how to solve this or write it the way they want it

jamesj · Answer

Look at the problem we just solved together and mimic the calculations.  It is exactly the same.

I also suggest you do not write E(16) for 2006; instead, keep the variable equal to the year, E(2006).

anonymous · Answer

You know that E(0) is 69.9 years. That will help you get your equation. If $$E(t) = at + b$$, plug in t=0: $$E(0) = a(0) + b = 69.9$$, so b = 69.9.

Next, you know that E(5) = 72.8 [E(5) being the life expectancy in 1995]. Use this to find a: $$E(t) = at + 69.9$$$$E(5) = a(5) + 69.9 = 72.8$$, so you can solve for a as well. Then, you just need to let t=16! $$E(16) = a(16) + 69.9$$, which will yield your answer.

anonymous · Answer

I had to step out for a minute. thanks you guys