Curriculum placement
Grade 6. This describes the skill, not a learner estimate.
Area of triangles and other polygons
Find triangle and polygon areas by decomposition
Problem types
- Write an equation for area or volume with fractions
- Triangle area
- Area by decomposition
- Area of the pieces
- Which area expression
Builds on
- Multiplying fractions
- Area of a rectangle
- Composing shapes · Useful idea
Cutting a polygon into rectangles and triangles uses the same decomposing idea as taking a shape apart into smaller shapes.
Leads to
Related skills
- Area and perimeter problems · Shared foundations
- Circumference and area of a circle · Shared foundations
- Dividing fractions · Shared foundations
- Volume with fractional edge lengths · Shared foundations
- Volume in unit cubes · Shared foundations
Open the interactive map to explore lessons and skill connections.