A vehicular travels a distance of 5t^4-10t^2+6 miles in t+2 minutes

The complete question is

A vehicle travels a distance of 5t^4-10t^2+6 miles in t+2 minutes how fast is the vehicles speed

we know that

speed=distance/time

distance = 5t^4-10t^2+6 miles

time=t+2 minutes

so

You have to divide the distance by the time

speed=[5t^4-10t^2+6]/[t+2] miles/minute

the answer is

the speed is [5t^4-10t^2+6]/[t+2] miles/minute