The function which relates the distance traveled d to the time t as the train travels at a constant speed is,
[tex]f(t)=210t,\\d=210t[/tex]
The speed of a body is the rate at which it covers the total distance is in the time taken. The speed of the body is given as,
[tex]s=\dfrac{d}{t}[/tex]
Here, (d) is the distance travelled by the body and (t) is time taken by the body to cover that distance.
A train leaves the station at time t=0. Traveling at a constant speed, the train travels 420 kilometers in 2 hours.
If the train travels 420 kilometers in 2 hours. Then by the above relation, the distance it travel in one hour will be,
[tex]d=\dfrac{420}{2}\\d=210\rm\; km[/tex]
As the train with constant speed travels 210 km per hour. Thus the linear function for this condition can be modeled as,
[tex]s=\dfrac{d}{t}\\210=\dfrac{d}{t}\\d=210t[/tex]
In the function of time,
[tex]f(t)=210t[/tex]
Thus, the function which relates the distance traveled d to the time t as the train travels at a constant speed is,
[tex]f(t)=210t,\\d=210t[/tex]
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