Question

In a quadrilateral, define each of the following:
(i) Sides
(ii) Vertices
(iii) Angles
(iv) Diagonals
(v) Adjacent angles
(vi) Adjacent sides
(vii) Opposite sides
(viii) Opposite angles
(ix) Interior
(x) Exterior

Answer 1

(i) Sides: In a quadrilateral ABCD, form line segments AB, BC, Cd and DA are called sides of the quadrilateral.
(ii) Vertices: The ends points are are called the vertices of the quadrilateral. Here, in the figure, A, B, C and D are its vertices.
(iii) Angles: A quadrilateral has four angles which are at their vertices. In the figure, $\angle A,\angle B,\angle C$ and $\angle D$ are its angles.
(iv) Diagonals : The line segment joining the opposite vertices is called diagonal. A quadrilateral has two diagonals.
(v) Adjacent Angles: The angles having a common arm (side) are called adjacent angles.
(vi) Adjacemt sides: If two sides of a quadrilateral have a common end-point, these are called adjacent sides.
(vii) Opposite sides: If two sides do not have a common end-point of a quadrilateral, they are called opposite sides.
(viii) Opposite angles: The angles which are not adjacent are called opposite angles.
(ix) Interior: The region which is surrounded by the sides of the quadrilateral ia called its interior.
(x) Exterior: The part of the plane made up by all points as they not enclosed by the quadrilateral, is called its exterior.