A ruled semicircle used for measuring and drawing angles.
Protractor
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Cite this as:
Weisstein, Eric W. "Protractor." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Protractor.html
A ruled semicircle used for measuring and drawing angles.
Weisstein, Eric W. "Protractor." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Protractor.html