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5 terms

Circle Formulae

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Area of a Circle
πr²
Circumference of a Circle
2πr or πd
Measure of an Angle on a Circle
½(measure of intercepted arc)
Measure of an Angle inside a Circle
½(measure of intercepted arc + measure of vertical angle's intercepted arc)
Measure of an Angle outside a Circle
½(measure of large intercepted arc - measure of small intercepted arc)