The following diagram shows the same parallel lines, ℓ
ℓ
and m
m
, intersected by the same transversal.

a transversal line intersects lines l and m. more information about the lines and angles is given in the long description.
© 2017 flipswitch. created using geogebra.

select all of the angle pairs that are alternate interior angles.

∠4
∠
4
and ∠6
∠
6
∠4
∠
4
and ∠5
∠
5
∠2
∠
2
and ∠7
∠
7
∠3
∠
3
and ∠6
∠
6
∠1
∠
1
and ∠6