CIRCLES 2

Find the value of y in the figure below if O is the centre of the circle. [diagram not to scale]

Solution

Angle at the centre = 2 x (angle at the circumference)

= 2 x (y)

=2y

Angle 2y and 7y are opposite angles. They add up to 360⁰.

Therefore 

2y + 7y = 360⁰

9y = 360⁰

9y = 360⁰ 

9         9 

y = 40⁰          

Hence y = 40⁰          

TRY THIS………….

Find the value of y in the figure below if O is the centre of the circle. [diagram not to scale]