Question

4. In the given figure, O is the centre of the circle. Find angle ACB. if angle aob=140​

Answer 1

Answer:

since the angle oab and oba are equal and 90° because it is a theroem

Step-by-step explanation:

so angle acb= 360- 140- 90-90 =40°

Answer 2

Answer:

110 degrees

see construct a line joining OC

you will notice that triangle OAC is an isoscles triangle since side OC and OA are equal being the radius of the same circle.

in triangle OAC angle AOC will be 140/2=70degree

now find angle OCA using the angle sum property

it comes out to be 55 degree

similarly angle OBC will also be 55 degrees

so your answer is 55+55=110 degrees

you can also confirm it with the angle sum property of a quadrilateral

140+110+55+55=360

so answer is 110 degrees