Direct Variation: Distance-Speed Relationship

Question:
Two cars travel at constant speeds. Car A travels 156 miles in 3 hours, and Car B travels 117 miles in 2.25 hours. Write a direct variation equation for each car relating distance d to time t. Which car is faster? At their respective constant speeds, how much farther will the faster car travel in 5 hours compared to the slower car?

Direct Variation: Distance-Speed Relationship

This lesson uses two cars traveling at constant speeds to build direct variation equations of the form d = k·t, where k is the constant of variation (speed in mph). Students compute k for each car, compare speeds, graph the equations, and calculate distances over a given time interval.

In this lesson, you will learn to:
• Write a direct variation equation $d = k \cdot t$ by computing the constant of variation $k = \frac{d}{t}$ from given data.
• Compare constants of variation to determine which relati