Enter the coordinate points and slopes of two dependent lines into the calculator to calculate a third value P, using bi-linear interpolation.

## Double Interpolation Formula

The following equation can be used to calculate a value from a double interpolation.

## What is double interpolation?

Double interpolation is a term used in mathematics to describe values that are dependent on two different variables or functions. For example, if an object C that relies on the states of both A and B and the states of A & B can be represented by functions, then the states of C can be calculated using double interpolation.