Area of Semicircles and Sectors

The ground covered by a shape cut evenly from a circle is found. A semicircle divides one whole circle by 2, a quarter circle takes a central angle of 90 degrees, and a sector takes angles from 30 to 120 degrees into the expression. Calculation carrying a drawing with measurements, and word problems opening from scenes such as a mat or a cookie, stand in equal numbers.

An arc is a length found from the diameter, and it carries no stage multiplying the radius by itself as an area does. Because a sector brings questions asking for the area and questions asking for the length of the arc, papers appear that put the same expression to both. The unit on the answer parts there too.

To Area of a Circle (Basics), which produced one whole circle as it stood, the share of a central angle has been added. Adding and subtracting the parts found here into one shape carries over into Composite Figures (Addition and Subtraction).