Constructions

Construction of Bisectors

• Construct a perpendicular bisector

• Construct an angle bisector

Construction of Triangles

Remember: ALWAYS SKETCH the shape before you start to construct!

• Construct a Triangle (SSS criterion)

• Construct a Triangle (SAS criterion)

• Construct a Triangle (ASA criterion)

• Special case: TWO POSSIBLE Triangles
• This happen when the angle given is not an "including" angle.

Construction of Quadrilaterals

Remember: ALWAYS SKETCH the shape before you start to construct!
   

Click here for the worksheet:  Worksheet

Example 1

Example 2

Example 3

Classwork

Construct a perpendicular line

(a) Perpendicular to a point on a line

(b) Perpendicular from a point to a line

Construct a pair of parallel lines

Inscribed circle of a triangle

Hint: Centre of an inscribed circle of a triangle is EQUIDISTANT to the sides of the triangle.

Circumscribed circle of a triangle

Hint: Centre of an circumscribed circle of a triangle is EQUIDISTANT to the vertices of the triangle.