Question

The diagram shows a circle with centre O.

A, B, C & D lie on the circumference of this circle.
Given that AC is a diameter of the circle and ∠DCA = 51° and ∠BCA = 26°, find the size of ∠DAB as highlighted in the diagram.

Answer 1

Answer is 103’

CDA AND ABC ARE 90’ due to it being formed by the diameter


So,
ACB + BAC + ABC = 180
Thus BAC=64’

DCA + CDA + CAD = 180’
CAD=39’

BAC + CAD = 103’ = DAB