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Question
If opposite angles of a quadrilateral are equal, it must be a parallelogram.
Options
True
False
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Solution
This statement is True.
Explanation:

⇒ Let ABCD be a parallelogram, with A = α and B = β.
We have to prove that C = α and D = β.
⇒ α + β = 180° (co-interior angles, AD || BC),
⇒ ∠C = α (co-interior angles, AB || DC)
⇒ ∠D = β (co-interior angles, AB || DC).
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