Question

3. In a quadrilateral ABCD, <A = 65° and ,<B = 85°. If <C and <D are equal in measure,
find their values.
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Answer 1

Total of angles of a quadrilateral is 360°

<A + <B + <C + <D = 360°

65° + 85° + <C + <D = 360°

Since measures of <C and <D is equal

<C = <D

65° + 85° + <C + <C = 360°

150° + 2<C = 360°

2<C = 360° - 150°

2<C = 210°

<C = 105° = <D