Question

15) From a point Q. length of tangent to a circle is 24cm and distance of Q from
centre is 25cm. Radius of circle is_cm.
(a)7
(b) 12
(c) 15
(d) 24.5​

Answer 1

Answer:

Explanation:

Given :

• Length of a tangent (RQ) = 24 cm
• Distance from centre (AQ) = 25 cm

To Find :

• Radius of a circle, RA.

Formula to be used :

• Pythagoras theorem, ie,,H^2 = P^2 + B^2

Solution :

In ∆ARQ , ∠ARQ = 90°

According to the pythagoras theorem,

H^2 = P^2 + B^2

.°. AQ^2 = AR^2 + RQ^2

⇒ 25^2 = AR^2 + 24^2

⇒ 625 = AR^2 + 576

⇒ -AR^2 = 576 - 625

⇒ -AR^2 = -49

⇒ AR^2 = 49

⇒ AR = 7 cm

Hence, The radius of circle is 7 cm.