Question

Look at the following figure and fill in the blanks :

In the figure, $l$ and $m$ are the parallel lines and $p$is a transversal.

Pairs of alternate exterior angles are :………………………..

Answer 1

Alternate exterior angles :

Two angles that lie on the opposite sides of the transversal and are placed on two different lines are called alternate exterior angles. If the two given lines are parallel (and intersected by a transversal) then these pairs of angles are always equal.

In the given figure Line $AB$ and Line $CD$ are parallel lined and they are intersected by the transversal $MN$. Here, the alternate exterior angle pairs are :$\angle 1,\angle 7$ and $\angle 2,\angle 8$. i.e. $\angle 1=\angle 7$ and $\angle 2=\angle 8$.

Similarly, as per the question :

$\angle 1,\angle 7$and $\angle 4,\angle 6$ are the two pairs of alternate exterior angles.

Hence pairs of alternate exterior angles are : $\angle 1,\angle 7$ and $\angle 4,\angle 6$.