In simple linear regression, the numbers of unknown constants are:

In simple linear regression, there are two unknown constants. These are the slope and the y-intercept.

Step 1: Understand the Simple Linear Regression Model The simple linear regression model is represented by the equation y = mx + b, where:

• y is the dependent variable (the variable we are trying to predict or estimate)
• x is the independent variable (the variable we are using to make the prediction)
• m is the slope of the regression line (it represents the effect x has on y)
• b is the y-intercept of the regression line (it is the value of y when x is 0)

Step 2: Identify the Unknown Constants In this model, the unknown constants are m (the slope) and b (the y-intercept). These are the parameters of the model that we need to estimate based on the data.

So, in simple linear regression, the number of unknown constants is 2.