In the figure, YX−→− is a tangent to circle O at point X. mXB=52∘ mXA=104∘ What is the measure of ∠XYA ?

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1 Answer
Mar 11, 2017

m/_XYA=26^@mXYA=26

Explanation:

Let us join OXOX, OAOA, OBOB and XAXA.
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As measure of arc XA=104^@XA=104, /_XOA=104^@XOA=104 and

m/_XBA=1/2xx104=52^@mXBA=12×104=52

Further, as measure of arc XB=52^@XB=52, m/_XOB=52^@mXOB=52 and

and m/_BXY=1/2xx52^@=26^@mBXY=12×52=26

Hence, m/_XYA=m/_XYB=m/_XBA-m/_BXY=52^@-26^@=26^@mXYA=mXYB=mXBAmBXY=5226=26