please help with rational and radical functions please, can you help?

Question

Using the famous Distance equals Rate times Time equation write a specific equation to describe traveling down the road at 65 miles per hour in a car.

Answer 1

The underlying formula is d = rt (distance equals rate times time). From d = rt , we get two other relationships: r = d/t and t = d/r . These problems come in many forms: two bodies traveling in opposite directions, two bodies traveling in the same direction, two bodies traveling away from each other or toward each other at right angles. Sometimes the bodies leave at the same time, sometimes one gets a head start. Usually they are traveling at different rates, or speeds. As in all applied problems, the units of measure must be consistent throughout the problem. For solving the problem atleast two inputs required.

Source: http://www.education.com/study-help/article/algebra-help-distance-problems/