Question

Question
When a window is open, the temperature in a room falls 5ºF every 15 minutes. Before the window is opened, the temperature was ​ 70ºF​ .

Use the Ray tool to make a graph that shows the temperature of the room, T, after the window has been open for m minutes.

Keyboard Instructions
Initial graph state
The horizontal axis goes from -4.5 to 47.5 with ticks spaced every 5 unit(s).
The vertical axis goes from -4.5 to 84.5 with ticks spaced every 5 unit(s).
Temperature vs. Time Window Is Open
Time (min)Temperature (°F)

Answer 1

Equation: T(m) = 70 − (1/3)m, for m ≥ 0.

Explanation and how to draw the ray:
- At m = 0, T = 70 → plot the starting point (0, 70).
- Slope = −1/3 °F per minute (temperature falls 1°F every 3 minutes, or 5°F every 15 minutes).
- Plot additional points: (15, 65), (30, 60), (45, 55).
- Draw a straight ray through these points starting at (0,70) and extending to the right (m ≥ 0).