In triangle XYZ, XY = YZ and ∠X = 78°. Find the value of ∠Y.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 24°.
In ΔXYZ, XY = YZ and m∠X = 78°
m∠X = m∠Z = 78°
So, m∠X + m∠Y + m∠Z = 180°
⇒ 78° + m∠Y + 78° = 180°
⇒ 156° + m∠Y = 180°
⇒ m∠Y = 180° - 156° = 24°
Therefore, the value of m∠Y is 24°.