Your teacher surveyed the class to determine the number of hours that each student spent on social media. Your teacher created a table and scatterplot graph that displayed the number of hours and the average final grade based on the hours, x, and the average final grade percentage, y, based on the hours. Using the equation of the trend line (equation) of the data is, y=-7.2x+98.9. Interpret the y-intercept. What is the average grade if a student was on social media for 0 hours?

The equation of the trend line is given as \( y = -7.2x + 98.9 \), where \( y \) represents the average final grade percentage and \( x \) represents the number of hours spent on social media.

The y-intercept of this equation is the value of \( y \) when \( x = 0 \). In this case, the y-intercept is \( 98.9 \).

Interpreting the y-intercept:

- The y-intercept indicates the average grade of a student who spends **0 hours** on social media.
- Therefore, if a student was on social media for 0 hours, the average final grade would be **98.9%**.

In summary, the average grade for a student not engaging in social media at all is 98.9%.