CK12 - Geometry

Area

Now we can buildon the rectangleformulato find areasof othershapes.

Parallelogram

Example 4

How couldwe find the area of this parallelogram?

Makeit into a rectangle

The rectangleis madeof the samepartsas the parallelogram,so their areasare the same.The area of

the rectangleis , so the area of the parallelogramis also.

Warning:Noticethat the height of the parallelogramis theperpendiculardistancebetweentwo parallel
sidesof the parallelogram,nota side of the parallelogram(unlessthe parallelogramis also a rectangle,of
course).

Areaof a Parallelogram

If a parallelogramhas base unitsand height units,then the area, , is squareunits.

Triangle

Example 5

How couldwe find the area of this triangle?