Q31 of 153 Page 148

Side BC of ΔABC has been produced to D on left hand side and to E on right hand side such that ∠ABD = 125° and ∠ACE = 130°. Then ∠A = ?

ABD + ABC = 180 (Linear pair of angles)


ABC = 180o – 125o=55o


ACE + ACB = 180 (Linear pair of angles)


ACB = 180o – 130o=50o


As we know that


ACB + ABC + BAC = 180o


BAC = 180 – 55 – 50


=75o

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In ΔABC, if ∠A – ∠B = 42° and ∠B – ∠C = 21°, then ∠B = ?

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In the given figure, ∠BAC = 30°, ∠ABC = 50° and ∠CDE = 40°. Then ∠AED = ?

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