This diagram of airport runway intersections shows two parallel runways. a taxiway crosses both runways.

how are < 7 and < 3 related?

a.
alternate interior angles
c.
corresponding angles
b.
same-side interior angles
d.
none of these

The 2 parallel runways, are "intersected" by another runway. 

The following pairs of angles are called :

1 and 5; 2 and 6; 3 and 7; 6 and 8.

Thus angles 7 and 3 are corresponding angles. 

Note: 7 and 3 are also called F angles, because of the shape F formed by those angles and the transversal.

b corresponding angles

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