The Circle
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A circle is a round shape. All the points on the edge, (the edge is called the circumference), are the same distance from the center. We use a large C to represent the circumference.
The diameter of a circle (we use a small d to represent the diameter) is the distance across the circle, passing through its center. It is a line that connects two points on the circle's circumference. The line must pass through the center.
The radius of a circle, (we use a small r to represent the radius), is the distance from the center of the circle to any point on its circumference. It is half the length of the diameter. Remember that the diameter is the distance across the circle through the center.
The diameter of a circle (we use a small d to represent the diameter) is the distance across the circle, passing through its center. It is a line that connects two points on the circle's circumference. The line must pass through the center.
The radius of a circle, (we use a small r to represent the radius), is the distance from the center of the circle to any point on its circumference. It is half the length of the diameter. Remember that the diameter is the distance across the circle through the center.
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Irregular Circle
The Semi-circle
A semi-circle is a perfectly symmetrical shape that represents exactly one-half of a full circle.
It is created by drawing a straight line, called the diameter, directly through the center of a circle from one side to the other.
This flat line serves as the straight base of the semi-circle, while the remaining curved line forms the rounded arch. You can spot this shape on both ends of Bookmark Two.
It is created by drawing a straight line, called the diameter, directly through the center of a circle from one side to the other.
This flat line serves as the straight base of the semi-circle, while the remaining curved line forms the rounded arch. You can spot this shape on both ends of Bookmark Two.