The Apothem The apothem a is the segment






















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The Apothem The apothem (a) is the segment drawn from the center of the polygon to the midpoint of the side (and perpendicular to the side)
Deriving the Formula - Squares The diagonals of the square divide it into four triangles with base s and height a. The area of each triangle is sa. Since there are 4 triangles, the total area is 4( )sa or (4 s)a. Since the perimeter (p) = 4 s the formula becomes A = ap
Deriving the Formula - Triangles Connecting the center of the equilateral triangle to each vertex creates three congruent triangles with area A = sa. Since there are three triangles, the total area is 3( )sa, or (3 s)a. Since the perimeter = 3 s, the formula may be written A = ap
Deriving the Formula - Regular Hexagons Connecting the center of the regular hexagon to each vertex creates six congruent triangles with area A = sa. Since there are six triangles, the total area is 6( )sa, or (6 s)a. Since the perimeter = 6 s, the formula may be written A = ap
Finding the apothem - Square The apothem of a square is one-half the length of the side. If as == 14, 15, sa == ? ? If a = 7. 5 s = 28
Find the apothem - Triangles The apothem of an equilateral triangle is the short leg of a 3060 -90 triangle where s/2 is the long leg. 60 30 Then a = (s/2)/ 3 90 or
Find the apothem - Triangles If. If s. If=ss 10, ==24, 18, a =aa? == ? ?
Find the side - Triangles If If the apothem is is 6 cm, the side = ? 2. 5 cm, the side = ?
Finding the apothem - Hexagons The apothem of a regular hexagon is the long leg of a 30 -60 -90 triangle. 30 60 Therefore, the apothem is (s/2) 90
Finding the apothem - hexagons If the side = 5 If the side = 12 the apothem = ?
Finding the side - hexagons If If the apothem == 16, 12, the side == ? ?
Finding the area - Squares a = 6 cm Find the area 2 A = 144 cm 2 2 AA= =50 cm 288 cm
Finding the Area - Triangles If a = 3 cm, find the area of the triangle
Finding the Area - Triangles If a = 5 cm, find the area of the triangle
Finding the Area - Triangles
Finding the Area - Triangles If the side of the triangle = 10 cm, find the area of the triangle
Finding the Area - Triangles
Finding the area - hexagons If the a = 6 cm, find the area of the hexagon.
Finding the area - hexagons
Finding the area - hexagons
Finding the area - hexagons