To help you with your questions, I would need to see the graph you are referring to, as the line of best fit and the data points directly influence the answers. Unfortunately, I can't view images or graphs directly. However, I can guide you on how to approach these questions.
1) Writing an Equation for the Line of Best Fit:
To write an equation for the line of best fit, you typically need two points on the line or the slope and the y-intercept. The general form of the equation for a line is:
\[ y = mx + b \]
where:
- \( y \) is the dependent variable (e.g., math grade),
- \( x \) is the independent variable (e.g., hours studied),
- \( m \) is the slope of the line (rise over run),
- \( b \) is the y-intercept (the value of \( y \) when \( x = 0 \)).
You can find the slope using:
\[ m = \frac{(y_2 - y_1)}{(x_2 - x_1)} \]
and use one point to solve for \( b \).
2) Making a Prediction for a Student Who Studies 6 Hours:
Once you have the equation of the line, you can substitute \( x = 6 \) into the equation to find the predicted math grade.
3) Making a Prediction for a Grade of 40%:
To find out how many hours a student needs to study to achieve a grade of 40%, you would set \( y = 40 \) in the equation and solve for \( x \):
\[ 40 = mx + b \]
Rearranging the equation to solve for \( x \):
\[ x = \frac{(40 - b)}{m} \]
If you can provide the specifics of the graph, such as the coordinates of points or the slope and intercept, I can assist you further in finding exact answers.