Posted by cat on .
The formula
R =−0.0026? + 4.0807
can be used to predict the world record, in minutes, for the 1500m run t years after 1900. Determine (in terms of an inequality) those years for which the world record will be less than 3.8 min.

algebra 
drwls,
Is ? supposed in your equation to be t?
If so, you need to solve
3.8 < 4.0807  0.0026 t
It can be rewritten
0.0026 t > 0.2807
Solve for t and add that to 1900.
The equation is not at all accurate. The men's world record for this distance became 3.325 minutes in 2004.
Perhaps the equation applies to the WOMEN's world recdrod time.
Please state your questions more carefully