In the adjoining figure, is a parallelogram in which and

Calculate (i) (ii) (iii) (iv)


In ABCD, and


(i) In ∆AOB,


BAO = 35°


AOB = COD = 105° …Vertically opposite angels
ABO = 180° − (35° + 105°) = 40° … Using Angle sum property of Triangle
(ii)
ODC and ABO are alternate angles for transversal BD
ODC = ABO = 40°
(iii)
ACB = CAD = 40°° …Alternate angles for transversal AC
(iv)
CBD = ABC ABD ...(1)


ABC = 180° − BAD …Adjacent angles are supplementary


ABC = 180° − 75° = 105°
CBD = 105° − ABD … as ABD = ABO
CBD = 105° − 40° = 65°


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