In this page, overview of construction of the following are provided
• a line segment
• a circle of given radius
• a semi circle of given radius
• a line by copying another line
• constructing an angle by copying another angle
Constructing a Line segment
To construct a line segment of length 66cm, the ruler is used.
Constructing a line Segment: Constructing a line can be achieved by one of the two methods.
• Construct a line and mark the length using a ruler.
• Construct a line and measure the length using a compass to mark an arc on the line.
Constructing a circle and semi-circle
To construct a circle of radius 33cm, a compass is used.?
Construction of a Circle : Measure the radius in a compass and mark a circle from the center point.
To construct a semi-circle of radius 33cm at point AA, a compass is used.
Constructing a Semicircle : Measure the radius using a compass and mark the semicircle from the center point.
Construction Line Segment by Copying
A line segment ¯PQ¯¯¯¯¯¯PQ is given. To copy the line segment ¯PQ¯¯¯¯¯¯PQ, a compass is used to measure the length of given line segment and mark that in another line.
Copying a line segment : Copy the length of the given line in a compass and construct an arc on a line.
Copying an angle
The following property helps to copy an angle using compass: "two triangles with identical sides have identical angles".
Given ∠BAC. To copy this angle, make a triangle of random sides △APQ. Copy the length of line segment ¯AQ to mark point L on the given line. Copy the lengths of line segments ¯AP and ¯QP to mark M from points X and L respectively. Join the points X and M. The angle ∠BAC is reproduced in ∠LXM.
Copying a Given Angle : Mark a triangle in the given angle and reproduce the sides of a triangle which copies the angle.
Construction of a line segment : The given length is measured using a ruler / scale and the line segment is marked.
Construction of a circle of given radius : The given radius is measured in a compass and the circle is drawn.
Construction of a semi circle of given radius : The given radius is measured in a compass and semi circle is drawn.
Construction of a line by copying another line : The length of the given line is measured using a compass and the line segment is marked.
Construction of an angle by copying another angle : A triangle is marked in the given angle and the sides of the triangle are reproduced to reproduce the angle.
The outline of material to learn "Construction / Practical Geometry at 6-8th Grade level" is as follows.
Note: click here for detailed outline of "constructions / practical geometry".
• Four Fundamenatl elements
→ Geometrical Instruments
→ Practical Geometry Fundamentals
• Basic Shapes
→ Copying Line and Circle
• Basic Consustruction
→ Construction of Perpendicular Bisector
→ Construction of Standard Angles
→ Construction of Triangles
• Quadrilateral Forms
→ Understanding Quadrilaterals
→ Construction of Quadrilaterals
→ Construction of Parallelograms
→ Construction of Rhombus
→ Construction of Trapezium
→ Construction of Kite
→ Construction of Rectangle
→ Construction of Square