In the given figure AB = DB and AC = DC. If ∠DBC = (2x - 4)° and ∠ABD = 58°, ∠ACB = (y + 15)° and ∠DCB = 63°, then the value of 2x + 5y is :

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Correct answer: B
Explanation
The correct answer is option 2 i.e. 273.
AB = DB and AC = DC
∠DBC = (2x - 4)°
∠ABD = 58°,
∠ACB = (y + 15)° and ∠DCB = 63°
If all three sides of the triangle are equivalent to the corresponding three sides of the other triangle, then both triangles are said to be congruent by the SSS rule.
Since AB = DB and AC = DC and BC is a common side
Therefore, triangles
So, ∠ABC = ∠ DBC = × ∠ABD = 58/2 = 29°
According to the given values, (2x - 4)° = 29
⇒ 2x = 33°
Also, angle ACB = angle DCB = 63°
⇒ (y + 15)° = 63°
⇒ y = 48°
Now, 2x + 5y = 33° + 240° = 273°