Answer:
55°
Explanation:
∠CGD is a vertical angle (thus congruent) with ∠FGA, which is the complement of ∠FGE. That complement is 90° -35° = 55°.
∠CGD is 55°
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You know ∠FGA and ∠FGE are complementary because ∠AGE is a right angle. The mark on ∠AGB tells you so.