Final answer:
Annie's regression model can be written as Y = a + bx.
Step-by-step explanation:
The regression model written as Y = a + bx represents Annie's regression model.
This equation is commonly used in linear regression, where Y is the dependent variable, a is the intercept, b is the slope, and x is the independent variable.
The equation allows us to predict the value of Y based on the values of x, and it assumes a linear relationship between the variables.