The document discusses the midpoint formula. It provides the formula for finding the midpoint between two points (x1, y1) and (x2, y2), which is to take the average of the x-coordinates and the average of the y-coordinates. An example is worked through to demonstrate finding the midpoint between points (2,3) and (5,7), which is (3.5,5). Another example finds the midpoint between points (3,15) and (12,9), which is (7.5,12). The document emphasizes that the midpoint formula provides a simpler way to find the point equidistant from two given points compared to using the distance formula.