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 \(b\).
The points that the line passes through approximately are:
- (0, 45)
- (2, 25)
- (3, 15)
- (4.5, 0)
First, let's calculate the slope \(m\) using two points, say (0, 45) and (4.5, 0).
The formula for the slope \(m\) between two points \((x_1, y_1)\) and \((x_2, y_2)\) is: \[ m = \frac{y_2 - y_1}{x_2 - x_1} \]
Using (0, 45) as \((x_1, y_1)\) and (4.5, 0) as \((x_2, y_2)\): \[ m = \frac{0 - 45}{4.5 - 0} = \frac{-45}{4.5} = -10 \]
Now that we have the slope, we can use one of the points to find the y-intercept \(b\). Using the point (0, 45): \[ y = mx + b \] Substitute \(m = -10\) and the coordinates of the point (0, 45): \[ 45 = -10(0) + b \] \[ b = 45 \]
Now we have both the slope and the y-intercept:
- Slope \(m = -10\)
- Y-intercept \(b = 45\)
The equation of the trend line in slope-intercept form is: \[ y = -10x + 45 \]
So the answer is: \[ y = -10x + 45 \]