Area of Complex Polygons and 3D Surface Area
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Objective
I can determine the area of complex polygons and the surface area of three-dimensional figures using decomposition and nets.
Part 1 of 3
Key concepts
3 concepts
- 1
To determine the area of intricate two-dimensional shapes, the strategy of decomposition involves breaking down an irregular polygon into simpler shapes like rectangles or triangles.
- 2
Calculating the surface area of a solid figure requires finding the total area of all its exterior faces, often by using a net which is a two-dimensional pattern.
- 3
A figure's net allows for clear identification of each face, and by computing the area of each component and summing them, the total surface area is precisely determined.
Part 2 of 3
Practice
7 questions
What is the primary strategy used to determine the area of an irregular or complex two-dimensional polygon?
Describe the steps you would take to find the total area of a complex polygon using the decomposition method.
Part 3 of 3
Exit ticket
Quick comprehension check
“An L-shaped polygon is created by taking a 10 cm by 8 cm rectangle and removing a 4 cm by 3 cm rectangular section from one of its corners. Determine the area of this complex polygon using decomposition. Show your steps. Next, consider a rectangular prism with a length of 7 cm, a width of 5 cm, and a height of 2 cm. Determine its total surface area, explaining how the concept of a net helps in this calculation and showing all calculations for each face.”
Sample answer included in the free materials
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