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Question 1

In OC, mAB= 72. Find m/_BCD.
A 72
B 108
C 144
D 180
and maybe 5 & 6 if ur feeling generous

Question 1 In OC, mAB= 72. Find m/_BCD. A 72 B 108 C 144 D 180 and maybe 5 & 6 if-example-1

1 Answer

6 votes

1) Because
\angle ACB is a central angle,
m\angle ACB=72^(\circ).

Since
\angle ACB and
\angle BCD are supplementary, they form a linear pair, and thus
m\angle BCD=180^(\circ)-72^(\circ)=\boxed{108^(\circ)}

5) Tangents drawn from an external common point are congruent, so CR=CP=8 and RB=BQ=4. This means that QA=11, and so PA=11 as well. Adding CP+PA, we get AC=19.

6) By the inscribed angle theorem, angle QPR measures 36 degrees.

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