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Question
If the angles A, B and C of ΔABC satisfy the relation B − A = C − B, then find the measure of ∠B.
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Solution
In the given ΔABC,
∠A, ∠B and ∠C satisfy the relation B - A = C - B
We need to fine the measure of ∠B.
As,
B - A = C - B
B + B = C + A
2B = C + A
2B - A = C ........(1)
Now, using the angle sum property of the triangle, we get,
A + B + C = 180°
2B - A + A +B = 180° (Using 1)
3B = 180°
`B = (180°) / 3`
= 60°
Therefore, ∠B = 60°
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