Question

the length of a tangent from a point A at distance 5 cm from the centre of the circle passes through the centre​

Answer 1

Answer:

Let AT be the tangent drawn from a point A to a circle with centre

O and OA=5 cm and AT=4 cm. Since tangent at a point is

perpendicular to the radius through the point of contact

∴OT⊥AT

∴ from right angled △OAT,

(OA)

2

=(OT)

2

+(TA)

2

⇒(5)

2

=(OT)

2

+(4)

2

⇒25−16=(OT)

2

⇒9=(OT)

2

⇒OT=3 cm

∴ radius of the circle =3 cm.

solution