The area of a semicircle is (?*R*R)/2. This means the radius of the semicircle is squared, multiplied by the constant pi, then divided by 2.
Know MoreA semicircle is half a circle. The diameter of the circle divides the circle into two equal semicircles. The formula for a semicircle is derived from the formula of the circle, only divided by two. An alternative method is to use the diameter, which is twice the length of the radius. Therefore, using the diameter of the circle, the formula for finding the area of one semicircle is (?*D*D)/4, where D is the diameter and is equal to 2R.
Learn MoreExamples of irregular solids include rocks, prisms, beans and screws. Each of these objects feature an irregular shape that is not composed of other recognized shapes.
Full Answer >A nine-sided polygon is commonly called a nonagon. This polygon, which has nine edges, or vertices, is also called an enneagon. The term enneagon is preferable, but less popular than the name nonagon because the latter is simpler to spell and pronounce, according to Wolfram MathWorld.
Full Answer >A dodecagon, a polygon with 12 sides and 12 vertices, has 54 distinct diagonals. The formula for determining the number of diagonals of an n-sided polygon is n(n - 3)/2; thus, a dodecagon has 12(12 - 3)/2 = 12(9)/2 = 108/2 = 54 diagonals.
Full Answer >A perpendicular bisector is a line that cuts across the midpoint of a given line segment at a 90-degree angle. It divides the line segment into two equal parts. A common method for drawing perpendicular bisectors uses a compass and straight edge or ruler.
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