Taking O as centre, draw an arc ‘AC’ with radius ‘r’. Cut the arc ‘AC’ at ‘B’, with centre ‘A’ and radius ‘r’. If ‘AB’ is joined in a straight line, what will be the ∠BAO (in degrees)?
The length of ‘AB’ is ‘r’(We took 'r' as the radius for drawing an arc to cut arc 'AC'). ‘OA’ and ‘OB’ are radii of the circle. Therefore △OAB is a equilateral triangle and internal angle ∠BAO=60∘.