not sure how to solve this...can anyone please help?

[ckwittymama]

In 1960, the life expectancy in the UK was 71.1 years. In 2008, it was 79.9 years. Let F(t) = life expectancy and t = the number of years since 1960.
a) Find a linear function that fits the data.
b) Use the function of Part (a) to estimate the life expectancy in 2010.

Show your work not just the final answer.

 

[mmm4444bot]

Have you learned yet how to write the equation of a line, when you know the coordinates of two points on that line?

They've given you the coordinates of two points; part (a) wants you to write the equation for the line that passes through them.

Part (b) wants you to use your equation to answer another question.


In this word problem, the coordinates represent (number of years since 1960, life expectancy).

So, one point on this line is (0, 71.1) because, in 1960, the number of years since 1960 is zero and the associated life expectancy we're told is 71.1.


What are the coordinates given by the data for 2008?


Please show your work using these two pairs of coordinates to find the equation of the line.

If you need a lesson on how to find the equation of a line using the coordinates of two points, here is one. The first example does not require you to calculate the slope, but the second example does. It is labeled "Find the equation of the line that passes through the points (–2, 4) and (1, 2)."

Please feel free to ask specific questions about anything that you do not understand.

 

[mmm4444bot]

By the way, instead of the symbols x and y, your example uses function notation for y and they've changed the name of the independent variable from x to t.

For the equation (slope-intercept form) of a line in the xy-coordinate system:

y = mx + b

you have t instead of x, and

you have f(t) instead of y:

f(t) = mt + b

These symbols are just names.

You can work with (x,y) coordinates using y = mx + b, and make the switch back to f(t) = mt + b at the end.