Final answer:
The y-intercept of a function is identified by the constant term in the function's equation, such as the b in y = mx + b or the a in y = a + bx, and represents where the graph of the function intersects the y-axis.
Step-by-step explanation:
The y-intercept of a function is the point where the graph of the function intersects the y-axis. This occurs when the input value x is zero. To find the y-intercept using a given function, such as y = mx + b or y = a + bx, you simply look at the equation and identify the constant term, which represents the y-intercept. In the equations provided, b or a stand for the y-intercept.
For a linear equation in the form of y = -173.5 + 4.83X, you would identify the y-intercept by looking at the constant term, which is -173.5. This means the graph of this function would cross the y-axis at the point (0, -173.5).
For a different example, such as the equation ŷ = -266.8863 + 0.1656x, the y-intercept would be the constant -266.8863. Even if it may not make sense to have a zero value for x, such as the context of year 0 not existing in a time series, the y-intercept still provides valuable information about where the line begins on the y-axis for the equation of the best-fit line.