Question

A point P is 5cm from the centre of the circle. The length of the tangent drawn from P to the circle is 4 cm. Find the radius of the circle.​

Answer 1

Step-by-step explanation:

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.

Answer 2

Answer:

3 cm.

Step-by-step explanation:

(b)^2=(h)^2-(p)^2

(b)^2=(5)^2-(4)^2

(b)^2=25-16

(b)^2=9

(b)^2=(3)^2

b=3

So, the radius of the circle is 3 cm.