Proportional Relationship: This is when two quantities always have the same size in relation to each other. In our dog-walking analogy, if you double your walking speed, the distance covered also doubles.
Direct Variation: This describes a situation where an increase or decrease in one variable leads to a corresponding increase or decrease in another variable. Like if you walk faster (increase speed), you'll cover more distance (increase distance).
Slope-Intercept Form: It's an equation of a line that shows its slope and y-intercept. In our analogy, the slope could represent your walking speed and y-intercept could be your starting point.