Overlapping again
What shape is the overlap when you slide one of these shapes half way across another? Can you picture it in your head? Use the interactivity to check your visualisation.
Problem
You may want to look at Overlaps before you try this problem.
Here are some pairs of shapes:
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What overlap shape would you get if you overlapped them halfway across each other?
Here are some more pairs of shapes. What overlap shapes would you get this time?
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Which of these overlap shapes did you find?
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Getting Started
Can you imagine gradually moving one shape across the other one?
It might help to draw the shapes, or cut some out from tissue paper or overhead transparencies.
Student Solutions
We haven't had any correct solutions to this problem yet, but you can still send us your ideas - we'd love to hear from you.
Teachers' Resources
Why do this problem?
Key questions
Possible extension
Learners who need more of a challenge could try Quadrilaterals.
Possible support
Suggest trying this simpler version of the problem.