To find the equation of the trend line in slope-intercept form (y = mx + b), we need to determine the slope (m) and the y-intercept (b).
From the points given in the description:
- One point is (0, 30), which indicates that the y-intercept (b) is 30.
- Two other points provided are (15, 40) and (30, 50).
Now we can determine the slope (m) using these two points:
- Calculate the slope (m) using the formula: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \] Using the points (15, 40) and (30, 50): \[ m = \frac{50 - 40}{30 - 15} = \frac{10}{15} = \frac{2}{3} \]
With the slope \( m = \frac{2}{3} \) and the y-intercept \( b = 30 \), we can write the equation of the trend line as: \[ y = \frac{2}{3}x + 30 \]
Therefore, the correct response is: y = 2/3x + 30.