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A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaGeometry

Diameter of a circle

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha2 × radius

Lengths use linear units, areas use square units, and volumes use cubic units. Source: Geometry ↗

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More from Geometry Essentials

A few more worth knowing.

  1. 15Polygon with seven sidesRECALL
    Heptagon

    Its interior angles sum to 900°

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  2. 16Polygon with ten sidesRECALL
    Decagon

    A regular one has ten equal angles

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  3. 17Line from a circle's centre to its edgeRECALL
    Radius

    Half the diameter

    Open this card ↗