Calculate the areas of composite shapes (VCMMG312)
LO: To find area of composite shapes.
Know:
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the dimensions of 2-D shapes such as length and width (height).
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how to classify different 2-D shapes by their properties.
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what the formulas for calculating the area of different 2-D shapes.
Understand:
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That formulas can be used to quickly and efficiently find the area of composite shapes.
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That composite shapes can be broken down to simple 2-D shapes.
Do:
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I can find the area of composite shapes.
Elaborations
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understanding that partitioning composite shapes into rectangles and triangles is a strategy for solving problems involving area.
Area of Composite Shapes
Composite shapes are shapes that have a combination of 2-D shapes.
To find the area of composite shapes you just need to break down the shape into individual pieces and calculate their separate pieces then add them back together again to find a total area.
Finding the Area of Composite Shapes (alternative methods)
Another way of finding the area of composite shapes is to use a subtraction model.
I could break the shape to the right into 2 pieces and find the area of the square then the area of the rectangle.
Alternatively, I can find the area of the entire shape (16 x 12) then subtract the missing piece (in pink) from the larger piece.
Teaching Ideas
