Find the measure of the exterior angle.

108°

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the 2 opposite interior angles.

2a is an exterior angle, thus

2a = a + 10 + 44 = a + 54 ( subtract a from both sides )

a = 54

Thus 2a = 2 × 54 = 108° ← exterior angle

Line BC

Step-by-step explanation:

Opposite means whatever is exactly parallel to angle a.

In this case, we notice BC to satisfy that rule.

Hope this helps.

Good Luck