  ### Home > CALC > Chapter 2 > Lesson 2.4.1 > Problem2-138

2-138.

Examine these scenarios and pay attention to the units.

1. While walking to school, Jaime's distance from home (in miles) was $s(t) = 3t^2$ , where t is measured in hours. Sketch a graph of his distance. If it took Jaime $30$ minutes to walk to school, what was his average velocity? Explain how you got your solution.

This is a distance graph. Time, $t$, should be on the $x$-axis. (It usually is!) And distance, $s(t)$, should be on the $y$-axis. Sketch the graph of $s(t) = 3t^2$.

Note that this is the slope of the secant line that connects the points at $t = 0$ and $t = 5$.

2. While walking home, Jaime walked so that his velocity (in miles per hour) was $v(t) = -2t$, where $t$ is measured in hours. How long did it take him to get home?

Sketch a velocity graph of $v(t) = -2t$. Time, $t$, will be on the $x$-axis. Velocity, $v\left(t\right)$, will be on the $y$-axis. How can distance information be found on a velocity graph?