Module 89 : Quadrilaterals
QUADRILATERALS
- Sum of the angles of a quadrilateral is 360^0
Cut a sheet of paper in the form of a quadrilateral. Mark the four angles of the
vertices as A, B, C and D. Cut the quadrilateral into four pieces so that the angles A,
B, C and D get separated into four pieces. Now arrange the four pieces adjacent to
each other to form an angle of 360^0 , revealing the fact that the angle formed in a
quadrilateral is 360^0.
- Pentagon through knot
Cut a sheet of paper in the form of a strip for a suitable length and width say
30cm×4 cm. Insert one end of the paper into the other to form a knot and gently pull
the paper on both ends so that a pentagon is formed. Now fold the sides so that the
paper strip takes a fine pentagon shape.
A
B
D C
E
A
B
D C
A
B C
D
A + B + C + D = 360 o