ABCD is a parallelogram in which ∠DAC=40∘;∠BAC=30∘;∠DOC=105∘ ; then ∠CDO equals :
ABCD is a cyclic quadrilateral in which :
(i) BC || AD, ADC=110o and ∠BAC=50o. Find ∠DAC.
(ii) ∠DBC=80o and ∠BAC=40o. Find ∠BCD.
(iii) ∠BCD=100o and ABD=70o. Find ∠ADB.
The diagonals AC and BD of a parallelogram ABCD intersect each other at the point O such that ∠DAC=30∘ and ∠AOB=70∘. Then, ∠DBC= ?
(a) 40∘
(b) 35∘
(c) 45∘
(d) 50∘