Compound Area Calculations
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Objective
I can find the area of compound shapes by breaking them into smaller known figures
Part 1 of 4
Warm-up video
Math with Mr. J · 7:14Vetted channel
We don't generate video — this one is by Math with Mr. J on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
To find the area of an irregular polygon, you must decompose it into different shapes for which you know the area formulas, such as triangles and trapezoids.
- 2
The apothem is the distance from the center of a regular polygon to the side at a right angle, and it represents the height of the triangles formed when finding the area.
- 3
The area of a regular polygon can be found using the formula: Area = ½ × perimeter × apothem.
Part 3 of 4
Practice
4 questions
What is the first step in finding the area of a composite figure?
A composite figure is made of a rectangle and a square. The rectangle has a length of 8 cm and a width of 5 cm. The triangle has a base of 6 cm and a height of 4 cm. What is the area of the composite figure?
Part 4 of 4
Exit ticket
Quick comprehension check
“A compound shape is made of a rectangle and a square. The rectangle is 4 inches long and 2 inches wide. The square has sides of 3 inches. What is the total area of the compound shape? Show your work.”
Sample answer included in the free materials
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