document.write( "Question 311333: I need help with this problem please. In 1990, the life expectancy of males in a certain country was 61.1 years. In 1996, it was 63.5 years. Let E represent the life expectancy in year t and let t represent the number of years since 1990. The linear function E(t) that fits the data is E(t)= ?t + ?(round to the nearest tenth). Then use the fuunction to predict the life expectancy of males in 2009. E(19)=? (round to the nearest tenth). Please help me with this. Thank you very much. \n" ); document.write( "
Algebra.Com's Answer #222699 by ankor@dixie-net.com(22740)\"\" \"About 
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In 1990, the life expectancy of males in a certain country was 61.1 years.
\n" ); document.write( " In 1996, it was 63.5 years.
\n" ); document.write( " Let E represent the life expectancy in year t and let t represent the number of years since 1990.
\n" ); document.write( " The linear function E(t) that fits the data is E(t)= ?t + ?(round to the nearest tenth).
\n" ); document.write( " Then use the fuunction to predict the life expectancy of males in 2009.
\n" ); document.write( " E(19)=? (round to the nearest tenth).
\n" ); document.write( ":
\n" ); document.write( "Find the slope
\n" ); document.write( "In 1990; x1=0 and y1=61.1
\n" ); document.write( "In 1996; x2=6 and y2=63.5
\n" ); document.write( ":
\n" ); document.write( "Find the slope (m) using the slope equation: m = \"%28y2-y1%29%2F%28x2-x1%29\"
\n" ); document.write( "m = \"%2863.5-61.1%29%2F%286+-+0%29%29\" = \"%282.4%29%2F%286%29\" = .4
\n" ); document.write( ":
\n" ); document.write( "Use the point/slope formula to write the equation; y - y1 = m(x - x1)
\n" ); document.write( "y - 61.1 = .4(x - 0)
\n" ); document.write( "y = .4x + 61.1
\n" ); document.write( ":
\n" ); document.write( "therefore:
\n" ); document.write( "The Linear function E(t) that fits the data is.
\n" ); document.write( "E(t)= .4t + 61.1
\n" ); document.write( ":
\n" ); document.write( "Use the Function to predict the life expectancy of males in 2009.
\n" ); document.write( "This means t=19; substitute 19 for t in the equation
\n" ); document.write( "E(19)= .4(19) + 61.1
\n" ); document.write( "E(19)= 7.6 + 61.1
\n" ); document.write( "E(19)= 68.7 yrs is the life expectancy in 2009
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Did this method make some sense to you?\r
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