Question

In triangle ABC AB=20cm, angle A=50°, angle B=70° . Find the length of the side BC and AC?

Answer 1

Answer:

It is given that seg RM and seg RN are tangent segments touching the circle at M and N, respectively.

∴ ∠OMR = ∠ONR = 90º (Tangent at any point of a circle is perpendicular to the radius throught the point of contact)

OM = 5 cm and OR = 10 cm

In right ∆OMR,

OR2=OM2+MR2⇒MR=OR2−OM2−−−−−−−−−−√ ⇒MR=102−52−−−−−−−√⇒MR=100−25−−−−−−−√=75−−√=53