In the given figure , AD=8 cm AC= 6 cm and TB is the tangent at B to the circle with centre O.Find OT , if BT= 4 cm Share with your friends Share 7 Rajat Sethi answered this We know angle in a semicircle is 90°.∴∠CAD=90°Now, in right angled triangle CAD,CD2=AC2+AD2CD=62+82=100=10 cmCD is a diameter of given circle,Thus,radius=OA=OB=102=5 cmWe know, tangent is perpendicular to the radius at that point of contact.∴∠OBT=90°Now, in right angled triangle OBT,OT2=OB2+BT2⇒OT=52+42=41 cm 2 View Full Answer Rishi Agrawal answered this Srry to say but please recheck your question. It's incorrect. Let me tell you why:-Take triangle AOC and AODOC=OD (radii of circle)Angle AOC = AOD (90 degree each)AO = A0 (Common Side)By SAS TRIANGLE AOC AND AOD ARE CONGRUENTTHIS MEANS THAT THEIR CORRESPONDING PARTS SHOULD ALSO BE EQUAL. BUT AC IS NOT NOT EQUAL TO AD AS PER QUESTION WHICH CONTRADICTS THE CONGRUENCY OF THE TRIANGLEs -5
