This is a retouched picture, which means that it has been digitally altered from its original version. Modifications: new picture, some elements reused. The original can be viewed here: AdditionRules.svg: . Modifications made by Kismalac.
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{{Information |Description={{en|Signs multiplication rule explained via Coulomb force}} {{es|La regla de los signos de la multiplicación explicada mediante la fuerza de Coulomb}} |Source=*File:AdditionRules.svg |Date=2011-05-06 10:18 (UTC) |Author=