411 REFERENCE · Wikibooks
GCSE Mathematics/Area and Volume
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Area of a square
To work out the area of a square, take one side, and multiply it by itself, as all sides on a square are equal.
Area of a rectangle
To work out the area of a rectangle, multiply one of one of the sets of parallel sides, by one of the other set of parallel sides.
Area of a circle
To work out the area of a circle, use the formula
thumbnail|C = Circumference R = radius D = Diameter
.
In the equation, r, the radius is the line from the circumference of a circle (the outside) to the center point.