Respuesta :
Answer:
see explanation
Step-by-step explanation:
Since BD bisects ∠ ABC , then
∠ ABD = ∠ DBC , substitute values
3x + 4 = 55 ( subtract 4 from both sides )
3x = 51 ( divide both sides by 3 )
x = 17
Step-by-step explanation:
Statement Reason
BD bisects ∠ABC Given
m∠ABD = (3x + 4)°, m∠DBC = 55° Given
∠ABD ≅ ∠DBC Definition of angle bisector
3x + 4 = 55 Definition of congruence
3x = 51 Subtraction property
x = 51/3 Division property
x = 17 Proved