Circles are 2D shapes with one side and no corners. The circumference is always the same distance from the centre - the radius. Sectors, segments, arcs and chords are different parts of a circle.
The formula to calculate the area of a circle, with radius \(r\) is: \(\text{area of a circle} = \pi r^2\)
Example
Calculate the area of the clock face. Give your answer to one decimal place.
\(\text{Area} = \pi \times 8^2\)
Remember to use BODMASThis is the order in which arithmetic operations must be carried out. Brackets - Of - Divide - Multiply - Add - Subtract.. The radius must be squared first before multiplying by \(\pi\).
The exact value for the area is = \(64\pi\). Rounded to 1 decimal place, the area is 201.1 cm2.