Two postulatesthat applyto area are the AreaCongruencePostulateand the AreaAdditionPostulate.
AreaCongruencePostulate:If two polygons(or planefigures)are congruent,then their
areasare congruent.AreaAdditionPostulate:The surfacearea of a three-dimensionalfigureis the sum of
the areasof all of its non-overlappingparts.You can use a net and the AreaAdditionPostulateto find the surfacearea of a right prism.
Fromthe net, you can see that that the surfacearea of the entireprismequalsthe sum of the figuresthat
makeup the net:
Total surfacearea = areaA+ areaB+ areaC+ areaD+ areaE+ areaF
Usingthe formulafor the area of a rectangle,you can see that the area of rectangleA is:
squareunitsSimilarly, the areasof the otherrectanglesare insertedbackinto the equationabove.
Total surfacearea = areaA+ areaB+ areaC+ areaD+ areaE+ areaF