Option B:
The linear equation that best describes the model is y = 40x + 800.
Solution:
Take two points which exactly on the line.
Let the points are (0, 800) and (10, 1200).
Slope of the line:
m = 40
y-intercept of the line is where the line crosses at y-axis.
y-intercept (b) = 800
Equation of a line:
y = mx + b
y = 40x + 800
The linear equation that best describes the model is y = 40x + 800.
Option B is the correct answer.