A tool called a compass is needed to draw a circle. A compass has two points: a sharp point and a point that contains lead. The sharp point has a tip for marking the centre of a circle, while the drawing point contains lead or a pencil for drawing a circle or an arc.
To learn more about circles, see the following concept sheet: Circles.
A circle is defined by two features: its centre and its radius. They are the only two pieces of information required to draw this geometric figure.
These are the steps to draw a circle according to its center and a point.
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Open the compass to match the length of the radius (the distance between the centre and a given point) of the circle to be drawn.
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Place the sharp tip on the paper. This will be the centre of the circle.
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Trace the outline of a circle by rotating the compass around the sharp tip. The circle is finished once a full rotation of the compass is complete.
Here are represented the different steps to draw a circle.
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To construct a circle with three unaligned points, certain properties of a circle must be used. The most important is that the perpendicular bisectors of the circle’s chords intersect precisely at its centre.
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Using a ruler, connect the three points with 2 separate line segments to form 2 chords in the circle.
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Draw the perpendicular bisector for each of the chords.
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Place the compass’ sharp tip at the intersection point where the perpendicular bisectors meet, and place the compass’ pencil tip on one of the three points.
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Draw the circle.
f you follow these steps, the circle drawn is guaranteed to pass through the three given points.
Draw a circle that passes through points |\left(1,2\right),| |\left(3,4\right)| and |\left(4,1\right).|
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1. Relier les 3 points avec 2 segments distincts afin de former les 2 cordes du cercle.
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2. Tracer la médiatrice de chacune des cordes.
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3. Placer la pointe sèche du compas sur le point d'intersection des médiatrices et placer la pointe à mine du compas sur un des 3 points.
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4. Tracer le cercle.
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In geometry, an inscribed circle is a circle that is tangent to all sides of a polygon.
The following method can be used to construct an inscribed circle in triangle |ABC|. To draw an inscribed circle in a regular polygon, first draw the bisectors of each of the angles. Next, follow steps 4 and 5 as described below.
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Construct the bisector of angle |A.|
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Construct the bisector of angle |B.|
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Construct the bisector of angle |C.|
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Identify a radius perpendicular to one of the triangle’s sides.
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Use this radius to draw the circle with the compass.
To draw an inscribed circle, you must know how to construct a perpendicular bisector and a bisector using a compass.
Draw an inscribed circle in triangle |ABC.|
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In geometry, a circumscribed circle is a circle which passes through all the vertices of a polygon.
The following method can be used to construct a circumscribed circle on triangle |ABC.| To draw a circumscribed circle on a regular polygon, first draw the perpendicular bisectors of each of the sides. Next, follow steps 4 and 5 as described below.
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Construct the perpendicular bisector of line segment |AB.|
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Construct the perpendicular bisector of line segment |AC.|
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Construct the perpendicular bisector of line segment |BC.|
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Draw the circle by placing the compass’ sharp tip on the centre of the circle (the intersection point of the three perpendicular bisectors) and the pencil tip on one of the polygon’s vertices.
To draw a circumscribed circle, you must know how to construct a perpendicular bisector using a compass.
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