To determine the equation of the trend line in slope-intercept form (y = mx + b), we need to find the slope (m) and the y-intercept (b) from the points you provided.
From your description, the line passes approximately through the following points:
- (0, 45)
- (2, 25)
- (3, 15)
- (4.5, 0)
Let's start by calculating the slope (m) using the points (0, 45) and (4.5, 0):
The slope formula is: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
Using the points (0, 45) and (4.5, 0):
- \( (x_1, y_1) = (0, 45) \)
- \( (x_2, y_2) = (4.5, 0) \)
Now, plug in the values: \[ m = \frac{0 - 45}{4.5 - 0} = \frac{-45}{4.5} = -10 \]
Now that we have the slope (m = -10), we can use the y-intercept (b) from the point (0, 45) where the line crosses the y-axis. Thus, \( b = 45 \).
Now we can write the equation in slope-intercept form: \[ y = -10x + 45 \]
Thus, the equation of the trend line is: \[ y = -10x + 45 \]