<Dl> <Dd> A = s (square). </Dd> </Dl> <Dd> A = s (square). </Dd> <P> The formula for the area of a rectangle follows directly from the basic properties of area, and is sometimes taken as a definition or axiom . On the other hand, if geometry is developed before arithmetic, this formula can be used to define multiplication of real numbers . </P> <P> Most other simple formulas for area follow from the method of dissection . This involves cutting a shape into pieces, whose areas must sum to the area of the original shape . </P>

Sam is determining the area of a triangle