In a quadrilateral, define each of the following:

(i) Sides


(ii) Vertices


(iii) Angles


(iv) Diagonals


(v) Adjacent angles


(vi) Adjacents sides


(vii) Opposite sides


(viii) Opposite angles


(ix) Interior


(x) Exterior

Example:



(i) Sides: Sides are the edges of a quadrilateral. All the sides may have same of different length.


In the above figure AB, BC, CD and DA are sides.


(ii) Vertices


Vertices are the angular points where two sides or edges meet.


In the above figure vertices are A, B, C and D


(iii) Angles


Angle is the inclination inclination between two sides of a quadrilateral.


In the above figure angles are: ABC, BCA, CDA and DAB


(iv) Diagonals


Diagonals are the lines joining two opposite vertices of a quadrilateral.


In the above figure diagonals are: BD and AC


(v) Adjacent angles


Adjacent angles have one common arm.


In the above figure angles ABC, BCD are adjacent anges.


(vi) Adjacents sides


Adjacent sides make an angle.


In the above figure AB BC, BC CA, CD DA, DA AB are pairs of adjacent sides.


(vii) Opposite sides: Opposite sides don’t have anything in common like sides orv angles.


In the above figure AB CD, BC DA are the pairs of opposite sides.


(viii) Opposite angles


Opposite angles are made by non adjacent sides.


In the above figure angles A and C, angles B and D are opposite angles.


(ix) Interior


Interior means within the quadrilateral.



(x) Exterior


Exterior means outside of a quadrilateral. For example point B is exterior of quadrilateral.



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