# Algebra

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In 1995, the life expectancy of males in a certain country was 64.8 years. In 1999, it was 67.2 years. Let E represent the life ecpectancy in year t and let t represent the number of years since 1995.

E(t)= t+ (round to nearest tenth

Use the function to predict the life expectancy of males in 2006. E(11)=
(round to nearest tenth)

• Algebra -

In 1995--64.8 yrs
In 1999--67.2 yrs

To write the equation, use the points
1999 - 1995 = 4 yrs
1995--(0, 64.8)
1999--(4, 67.2)

Equation through two points,
y - y1 = (y2 - y1)/(x2 - x1) * (x - x1)
y - 64.8 = (67.2 - 64.8)/(4 - 0) * (x-0)
y - 64.8 = 2.4/4 x
y - 64.8 = 0.6x
y = 0.6x + 64.8

Since, the function should be E(t),
E(t) = 0.6t + 64.8

To find E(t) for 2006,
E(11) = 0.6(11) + 64.8
E(11) = ?

• Algebra -

Thank you so much for the help. Although still slightly confused I now have something to work with to figure out what I am doing. I have had such a difficult time with this class. If it wasn't for all of you guys I would be lost. Thanks again