I thought the answer was B. But it is actually D.. I dont understand how (1) only can be sufficient.. someone please help!
Thanks
Nikhil
Thanks
Nikhil
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Consider triangle COB has 2 equal sides, therefore two equal angles namely OBC and OCB let them both be X
Now triangle ABO will have two sides equal and hence two angles also namely BAO and BOA let them be Y.
Statement 1 :
COD= 60, we can write Y + BOC + 60 =180, Y+BOC = 120
from the stem we can figure out angle BOC in terms of X, BOC+2X=180, therefore BOC = 180-2X
replacing in the first equation we get: Y+180-2X=120 , 2X-Y = 60
Now we know angle ABO is external angle for triangle BOC, therefore ABO = X+BOC
ABO = X + 180 - 2X, ABO = 180 -X
ABO from triangle AOB can be written as : ABO=180-2Y, therefore equating both ABO we get: 180-2Y = 180-X, therefore X = 2Y.
Now we have two equations with X and Y you can solve for BOTH, Hence Statement 1 sufficient.
