Area of Composite and Irregular Shapes

For irregular shapes, decompose them into basic shapes you know: 1. Identify rectangles, triangles, semicircles, trapezoids within the shape 2. Calculate each area separately 3. Add areas if the shape is a combination, subtract if parts are cut out Alternatively, enclose the shape in a rectangle and subtract the parts outside.

Example: An L-shaped room can be split into two rectangles: one 10 ft × 6 ft and one 4 ft × 8 ft. What is the total area?

On shaded region problems, area of shaded = area of outer shape − area of inner shape. This is the most common composite area question type on the SAT.