Find the relationship that survives changes of shape, size and direction, then check a new member.
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First lesson in this subject: Complete the angle sum
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These figures vary in their outline shape, size and direction. Look for a relationship that remains true in all three.
In each example, the smaller outline is completely inside the larger one. There is a visible gap between their boundaries. Turning the whole figure does not change that relationship.
You are reading the opening. Members read every lesson and guide in full. A free account reads the first lesson in each subject in full.
You are reading the opening. Your free account reads the first lesson in each subject in full. Members read every lesson and guide in full.
First lesson in this subject: Complete the angle sum
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Practice · Infer a shared geometric relationship from three examples, then choose the new figure that belongs.
Book · Explore measurements, transformations, coordinates and geometric relationships through diagrams and worked examples.
Previous lesson · Use the central angle to take the same fraction of circumference or circle area.
Next lesson · Include the larger triangles and rectangles formed by joining small regions, and avoid counting an outline twice.
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