These resources have been reviewed and selected by STEM Learning’s team of education specialists for factual accuracy and relevance to teaching STEM subjects in UK schools.


Act 1

A square and circle are shown. Initially the square is smaller than the circle. The two shapes then slide along a line with the square increasing in size and the circle decreasing. When do the circle and square have equal area?

Act 2

A second animation shows the same event as the first video, but this time with a scale drawn along the line.

Act 3

The answer is revealed in the form of an animation that adds a y-axis showing area to the scene.

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