Question

The chords AB subtends an angle AOB equal to 60 degree at the centre of the circle. If OA= 7cm , then find the length of AB

Answer 1

Answer:

(1) In the given figure, OA and OB are the radii of the circle.

OA=OB=AB (Given)

∴△OAB is an equilateral triangle.

⇒∠AOB=∠OAB=∠OBA=60

o

Thus, the measure of ∠AOB is 60

o

.

(2) The measure of an angle subtended by an arc at a point on the circle is half of the measure of the angle subtended by the arc at the centre.

∠ACB=

2

1

∠AOB=

2

1

60o=30

o

Thus, the measure of ∠ACBis30

o

.

(3) m(arcAB)=∠AOB=60

o

(Measure of an arc is the measure of its corresponding central angle)

Thus, the measure of arc AB is 60

o

.

(4) m(arcACB)=360

o

- m(arcAB)=360

o

−60

o

=300

o

Thus, the measure of arc ACB is 300

o

.

Answer 2

Answer:

Hii...

Tnx for free points......