Diagonals of a quadrilateral ABCD bisect each other. If ÐA = 35°, determine ÐB.
Given: 
A = 35°
∵ diagonals of the quadrilateral ABCD bisect each other
∴ it is a parallelogram
⇒ 
A + 
B = 180°
⇒ 35° + 
B = 180°
⇒ 
B = 180° – 35°
⇒ 
B = 145°
Hence, 
B = 145°.
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