7th Grade · Geometry

Decompose

7.G.B.6

Definition

To break a complex geometric figure into two or more simpler shapes. Used to find area of composite figures by adding (or subtracting) the areas of the simpler parts.

Examples

  • Split a figure into two rectangles: 32m² + 15m² = 47m².
  • Or use large rectangle minus missing piece for the same total.

Key rule

There is more than one way to decompose — choose the easiest for the figure.

Memory hook

Cut it into shapes you can measure.