Q5 of 69 Page 9

If the angles A, B and C of Δ ABC satisfy the relation B – A = C – B, then find the measure of ∠B.

Given,

In ABC,


B - A = C - B


B + B = A + C


2B = A + C (i)


Now,


A + B + C = 180°


B = 180 - (A + C) (ii)


Using (i) in (ii), we get


B = 180 - 2B


3B = 180°


B = 60°


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