Answer:
45°
Step-by-step explanation:
Two diagonals of a square intersect at right angle, I.e., 90°
BD and AC are two such diagonals of the square ABCD.
Since, they intersect at 90°:
∠DEC = 90°
We're given the value of ∠ECD and that is 45°
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Observing Triangle EDC:
Sum of all angles in a triangle = 180°
=> ∠DEC + ∠ECD + ∠EDC = 180°
=> 90 + 45 + ∠EDC = 180°
=> 135 + ∠EDC = 180
=> ∠EDC = 180 - 135
=> ∠EDC = 45
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Answer:
Hence, we know the value of ∠EDC and that is 45°
