This is circle based question from Chapter name- circles
Topic – Angle properties of circles
Chapter number- 15
It is given that , O is the centre of the circle and AB is a tangent at B. If AB = 15 cm and AC = 7.5 cm,
Then we have to find the radius of the circle. (b) In the figure given , from an external point P, tangents PA and PB are drawn to a circle.
It is also given that CE is a tangent to the circle at D. If AP = 15 cm, now we have to find the perimeter of the triangle PEC.
ICSE Avichal publication
Understanding ICSE Mathematics
Question no 8
Solution:
(i) Join OB
∠OBA = 90°
(Radius through the point of contact is
perpendicular to the tangent)