To determine the equation of the trend line in slope-intercept form (y = mx + b), we need to identify the slope (m) and the y-intercept (b) using the points that the line passes through.
Looking at the points given:
- (0, 30)
- (15, 40)
- (30, 50)
First, let's calculate the slope (m) between two points, for example (0, 30) and (15, 40):
\[ m = \frac{y_2 - y_1}{x_2 - x_1} = \frac{40 - 30}{15 - 0} = \frac{10}{15} = \frac{2}{3} \]
So the slope (m) is \(\frac{2}{3}\).
Next, we can use the y-intercept from the point (0, 30), where \(b = 30\).
Now we can write the equation of the trend line:
\[ y = \frac{2}{3}x + 30 \]
Hence, the correct answer from your options is:
y = \frac{2}{3}x + 30