SOLUTION: In 1920, the record for a certain race was 45.5 sec. In 1950, it was 45.2 sec. Let R(t)=the record in the race and t=the number of years since 1920. a) Find a linear function

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: In 1920, the record for a certain race was 45.5 sec. In 1950, it was 45.2 sec. Let R(t)=the record in the race and t=the number of years since 1920. a) Find a linear function       Log On


   



Question 135865: In 1920, the record for a certain race was 45.5 sec. In 1950, it was 45.2 sec. Let
R(t)=the record in the race and t=the number of years since 1920.
a) Find a linear function that fits the data.
b) Use the function in (a) to predict the record in 2003 and in 2006.
c) Find the year when the record will be 44.6 sec.
Find a linear function that fits the data.
R(t)=?
Can you please help me with this?

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
The first key is that t must be the number of years since 1920, so 1920 represents year 0, and 1950 represents year 30.

Now you have two data points
t = 0, R(t) = 45.5
t = 30, R(t) = 45.2

Therefore, you can plot two points on your graph: (0,45.5) and (30,45.2)

Use the two-point form of a line to derive the equation that passes through the two points. y-y%5B1%5D=%28%28y%5B1%5D-y%5B2%5D%29%2F%28x%5B1%5D-x%5B2%5D%29%29%28x-x%5B2%5D%29