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im not looking for an answer to a test, but i dont understand the formula of a the area of a circle and semicircle can someone please explain?

2 Answers

2 votes
Area of circle = πR²

Area of semi-circle = half of area of circle = πR²/2
User Bython
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So the area of a circle is the radius squared times pi. Pi = 3.141592... but it is usually shortened to 3.14. so basically, the area of a circle is pi * r^2. The area of a semicircle is half of this because a semicircle is half of a circle: (pi * r^2)/2
User Vittorio Cozzolino
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