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2 Circle A circle is the set of all points that are the same distance from a given point called the center.
3 Center The given point from which all points on a circle are the same distance.
4 Circumference The distance around a circle.
5 Diameter The diameter of a circle is a line segment that joins any two points on the circle and passes through the center of the circle.
6 Radius The radius of a circle is a line segment joining the center of the circle and any point on the circle.
7 diameter radius circumference diameter = 2 times radius of diameter radius =
8 8cm r = d ÷ 2 r = 8 ÷ 2 r = 4 cm 6 yd Find the radius. Find the diameter. d = 2r d = 2۰6 d = 12 yd
9 The relationship of the circumference and the diameter of a circle is called pi. The symbol for pi is.
10 Think of fact families Circumference
11 Circumference WORDS: The circumference of a circle is equal to pi times its diameter or pi times twice its radius. Symbols: or
12 Circumference Symbols: or
13 The circumference of a circle is a little more than three times its diameter. The circumference of a circle is a little more than six times its radius.
14 Use. Find the circumference. 8cm
15 Use. Find the circumference. 4 ft
16 Use. Find the circumference. 6 mm 6 x 6
17 Use. Find the circumference. 7 mm 6 x 7