In the most simple form, the polar second moment of area is a summation of the two planar second moments of area, formula_15 and formula_16. Using the Pythagorean theorem, the distance from axis formula_13, formula_12, can be broken into its formula_19 and formula_20 components, and the change in area, formula_21, broken into its formula_19 and formula_20 components, formula_24 and formula_25.