Question

a chord of a circle of radius 10 cm subtends a right angle at the centre. calculate the length of the chord in centimetre​

Answer 1

Answer:

20 only is correeeect

only

Answer 2

Answer:

The length of chord is 10

20

cm

Given a chord of a circle of radius 10 cm subtends a right angle at its centre.

we have to find the length of chord.

ΔAOB is right angled triangle

AO=OB=10 cm (Both radius)

∠AOB=90°

By Pythagoras theorem

(AB)^2=(AO)^2+(OB)^2(AB)

2

=(AO)

2

+(OB)

2

(AB)^2=(10)^2+(10)^2(AB)

2

=(10)

2

+(10)

2

(AB)^2=100+100=200(AB)

2

=100+100=200

AB=\sqrt{2\times 100}=10\sqrt{2}cmAB=

2×100

=10

20

cm