Answer:
The answer is:
Extrapolating.
Explanation:
The extrapolation of a data or a value is the rough estimation of the data point based on extending a given sequence of some values or data points beyond the value that are not provided.
In other way we can say:
In mathematics, extrapolation is the process of estimating the value of a variable beyond the range to which it is given or we can say beyond the original observation that is provided to us.
Hence, If you wanted to predict the value of the y variable when the x variable is 15, you would be extrapolating the data.