Vocab
Polygon 2 dimenstional shapes they are made of straight lines and the shape is closed all the lines connect
Regular Polygon a polygon with alll sides and angle in length
Perimeter the distace around 2 dimensioanl shape Circumference the distance around the edge of a circle think of it like the premiter of a circle
Diameter the distance of any line segment that passes through the center of the circle and whose endpionts are on the circle
Radius the distance from the center of a circle to the edge it is ½ of the diamter abou 3.14
Polygons
Triangle 3
Quadralateral square 4
Pentagon 5
Hexagon 6
Heptagon 7
Octagon 8
Nonagon 9
Decagon 10
Perimeter Formulas
Perimeter of a Triangle – P = a + b + c
Example: Find peerimeter of a triangle with sides 5 cm, 5 cm, and 7 cm.
P=a+b+c
5+5+7
=17 cm
Perimeter of Rectangle – P = L + L + W + W
Example: Find perimeter of a rectangle with L = 15 cm and W = 8 cm.
P=l+l+w+w
P=15+15+8+8
P=46cm
Perimeter of Square – P = s + s + s + s or 4s
Example: Find the perimeter of a square with each side 4.5 inches.
P=s+s+s+s
P=4.5+4.5+4.5+4.5
P=18in
Perimeter of Regular Polygon
Example: Find perimeter of regular pentagon with side of 10 cm.
P=s+s+s+s+s
10+10+10+10+10
P=50
Example: The perimeter of a regular hexagon is 18 cm p=s+s+s+s+s+s
18 6
6 6 s=3
Circumference
16637011366500Circumference Formula: c=23.14 r
C=3.14 d
Circumference the distance around the edge of a circle think of it like the premiter of a circle
Diameter the distance of any line segment that passes through the center of the circle and whose endpionts are on the circleRadius the distance from the center of a circle to the edge it is ½ of the diamter abou 3.14
23761701651000Find the Circumference:
C=3.14d
C=3.14 x 12
C=37.68cm 25126953556000Find the Circumference:
C=2 3.14 r
C=2×3 14×8
C=50.24
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