Answer:
1, 2, 5, 12, 13
Explanation:
∠1 = 90 is given, which is a right angle
∠3 = 90 as well because ∠1 and ∠3 are vertically opposite
∠3 = ∠8, because ∠1 and ∠8 are same side exterior angles, which are the same
Therefore ∠3 must be congruent to ∠8
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