Please solve q 69 ?

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1 Answer
May 13, 2018

#/_BTC=44^@#

Explanation:

.

#/_ACS=/_ABC=67^@# because they both face arc #AC# and are half the measure of that arc.

#/_BAC=90^@# because it is an inscribed angle facing the diameter of the circle.

#/_BCT=180^@-(90^@+67^@)=23^@#

#/_ABC=/_BTC+/_BCT# because #/_ABC# is the exterior angle of triangle #DeltaBTC#.

#67^@=/_BTC+23^@#

#/_BTC=67^@-23^@=44^@#