Composite shape

A composite shape can be split into familiar pieces. For area, add the areas of pieces that are present and subtract the areas of holes or cut-outs. Marking the shape into rectangles, triangles and circles before calculating helps to show which operation is needed.

A composite shape is assembled from familiar shapes such as rectangles, triangles and parts of circles. To find its perimeter, imagine tracing a finger once around the outside. Add every exposed straight or curved section exactly once.