Sides and angles of circumscribed triangle

Question

In the given figure below ‘O’ is the centre of the circumcircle of triangle ABC.

BC = 6.4 cm.∠A = 40º, ∠B = 80º, ∠C = 60º

(a) Find the diameter of the circle?

(b) Also find the length of the other two sides?

	40	60	80
sin	0.64	0.87	0.98
cos	0.77	0.50	0.17
tan	0.84	1.73	5.67

Answer 1

(a) As per the question,
In ΔABC

BC = a = 6.4 cm

AC = b

AB = c

∠A = 40°, ∠B = 80°, ∠C = 60°

Let ‘R‘ be the radius of circumcircle of ΔABC

Now the answer is justified.