Question

Q.11) In the figure, 'O' is the centre of the circle, angle
ABO= 20° and angle ACO= 30°, where A, B, C are points on the circle. What
is the value of x?
2
A
30°
/20
Х
C
B В​

Answer 1

Answer:

mark me brainliest please

Step-by-step explanation:

We have OB=OA(radii of the same circle)

Therefore OAB is an issosceles triangle

Angle OBA =AngleOAB

In Triangle OAB

Angle OAB =20 degree

Similarly in triangle OAC

Angle OAC =30 degree

Total angle BAC =50 degree

We know, BAC =halfBOC

Therefore angle boc =100 degree

Hence founded

Answer 2

Answer:

The answer is 100 degrees

Step-by-step explanation:

OA=OB (radii of the same circle)

therefore OAB is an isosceles triangle.

In Triangle OAC

Angle OCA=30 Degrees -- 1

In Triangle OAB

Angle OBA= 20 Degrees -- 2

Adding 1 and 2

20+30 degrees= 50 degrees

We know that angle subtended by an arc at the centre of a circle is double than that of any angle formed at remaining part of the circle (This is theorem 10.8)

2 Angle BAC = Angle BOC

Hence Angle BOC= 2 x 50= 100 degrees