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Question
The angles of quadrilateral are in whose AP common difference is 10° . Find the angles.
Solution
Let the required angles be (a -15 )° , (a -5)°, ( a+ 5)° as the common difference is 10 (given).
Then (a-15)° + ( a- 5 )° + ( a+5)° + (a + 15)° = 360°
⇒ 4a = 360
⇒ a=90
Hence, the required angles of a quadrilateral are
(90-15)°, (90-5)° , ( 90+5)° and (90+ 15 ) °, or 75° , 85° , 95 ° and 105° .
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