The diameter of a circle is 10 cm. If the distance of a chord from the centre of the circle be 4 cm, then the length of the chord is
Given : OB is the radius of circle = 5 cm and OC = 4 cm
To find : AB = ?
Solution : The line from the centre of the circle to the chord bisects it at right angle.
=> AC = BC = $$\frac{1}{2}$$ AB
In $$\triangle$$ OBC,
=> $$(BC)^2=(OB)^2-(OC)^2$$
=> $$(BC)^2=(5)^2-(4)^2$$
=> $$(BC)^2=25-16=9$$
=> $$BC=\sqrt{9}=3$$ cm
$$\therefore$$ AB = $$2 \times$$ BC
= $$2 \times 3=6$$ cm
=> Ans - (A)
Create a FREE account and get: