Question

In the given figure o is the center of the circle then find x.
Pls answer with explanation.......

Answer 1

BC is the diameter as it is a chord passing through the center.
so ∠boa + ∠aoc = 180°
⇒ ∠aoc = 180° - 70° = 110°
now, in triangle ACO
 OA = OC (equal radii)
so, ∠oac = ∠oca

also, ∠oac + ∠oca + ∠aoc =180°
⇒ 2 ∠oac = 180° - 110°
⇒ ∠oac = 70°/2 = 35°
therefore, x = 35°

Answer 2

Since Bc is the diameter it subtends a rigth angle so...∠BAC=90°
InΔOAB
OA=OB=radius of the circle
∴∠OAB=∠OBA(angles in an isoscles Δ)
∠AOB+∠OAB+∠OBA=180°
∠OAB=55°
∠CAD=x=90-55=35°
ans...therefore x=35°