Question

In the adjoining figure, ABCD is a quadrilateral.

(i) How many pairs of adjacent sides are there? Name them.

(ii) How many pairs of opposite sides are there? Name them.

(iii) How many pairs of adjacent angles are there? Name them.

(iv) How many pairs of opposite angles are there? Name them.

(v) How many diagonals are there? Name them.

Answer 1

(i) Adjacent sides is nothing but two sides of a quadrilateral having same end

i.e. there are four pairs of adjacent sides. They are

(AB, BC), (BC, CD), (CD, DA) and (DA, AB)

(ii) Two sides of a quadrilateral have same end point are called opposite sides.

There are two opposite sides. They are

(AB, DC), (AD, BC)

(iii) When two angles of quadrilateral shares the common arm it is called ad adjacent angles.

There are four adjacent angles. They are

(∠A, ∠B), (∠B, ∠C), (∠C, ∠D) and (∠D, ∠A)

(iii) When angles of a quadrilateral are not adjacent ten it is called as opposite angles.

There are two pairs of opposite angles. They are,

(∠A, ∠C), (∠B, ∠D)

(iv) A diagonal is a line segment which joins two opposite vertices.

Here there are 2 diagonals are there. They are

(AC, BD)