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.

Answer 1

(a)

Two sides of a quadrilateral are said to be adjacent sides of the quadrilateral, if they have a common end point

From the figure,

$(AB,BC),(BC,CD),(AB,AD)$ are the pair of adjacent sides of quadrilateral.

(b)

Two sides of a quadrilateral are said to be opposite sides of the quadrilateral, if they are not adjacent.

From the figure,

$(AB,DC)$ and $(BC,AD)$ are the pair of opposite sides of the quadrilateral

(c)

Two angles of a quadrilateral are said to be a adjacent angles of the quadrilateral, if they have a side of the quadrilateral in common.

$(\angle A,\angle B),(\angle B,\angle C),(\angle C,\angle D),(\angle D,\angle A)$ are the pair of adjacent angles of quadrilateral.

(d)

Two angles of a quadrilateral are said to be opposite angles of the quadrilateral, if they are adjacent.

$(\angle A,\angle C),(\angle B,\angle D)$ are the pair of opposite angles of quadrilateral