Please solve q 69 ?

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1 Answer
May 13, 2018

/_BTC=44^@BTC=44

Explanation:

.

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

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

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

/_ABC=/_BTC+/_BCTABC=BTC+BCT because /_ABCABC is the exterior angle of triangle DeltaBTC.

67^@=/_BTC+23^@

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