Answer:
63°
Explanation:
Knowing that opposite angles are equivalent, we can easily say that ∠3 is equivalent to 63°. ∠1 and ∠4 are the complements of the given angle and ∠3, so their measures are also the same and are equivalent to 180°-63°=117°.
Since the two horizontal lines are parallel, ∠6 is equivalent to ∠3, so it too is 63°. Its complements, ∠5 and ∠8, are thus equivalent to the complements of ∠1 and ∠4, and thus they are 117°. Lastly, since opposite angles are equivalent, ∠6 is equivalent to ∠7, and so ∠7 is also 63°.