Answer:
∠ 1 = 81° , ∠ 4 = 99°
Explanation:
∠ 1 and ∠ 6 are same- side exterior angles and sum to 180° , that is
∠ 1 + ∠ 6 = 180° ( substitute ∠ 6 = 99° )
∠ 1 + 99° = 180° ( subtract 99° from both sides )
∠ 1 = 81°
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∠ 4 and ∠ 6 are alternate exterior angles and are congruent ( equal) , then
∠ 4 = ∠ 6 = 99°