Raymond is investigating how long his phone's battery lasts (in hours) for various brightness levels (on a scale of 0-100). His data is displayed in the table and graph below.
| Brightness Level (x) | Hours (y) |
|---|---|
| 16 | 4.2 |
| 18 | 6.4 |
| 21 | 5.1 |
| 55 | 2.2 |
| 55 | 5.7 |
| 56 | 5.2 |
| 62 | 5 |
| 92 | 3.7 |
a) Find the equation for the line of best fit. Keep at least 3 decimals for each parameter in the equation. (You should begin by typing y=)
b) Interpret the slope in context.
c) What does the equation predict for the number of hours the phone will last at a brightness level of 46? hours