Respuesta :

1. ray BF bisects ∠ABC                   1. given

   m∠ABD = m∠CBE              

2. ∠ABF ≅ ∠ CBF                            2. angle bisector theorem

3. m∠ABF = m∠CBF                        3. definition of congruency

4. m∠ABF = m∠ABD + m∠DBF       4. angle addition postulate

  m∠CBF = m∠CBE + m∠EBF

5. m∠ABF = m∠CBE + m∠DBF      5. substitution (s1: m∠ABD = m∠CBE)

6. m∠CBF = m∠CBE + m∠DBF       6. substitution (s3: ∠ABF = ∠ CBF)

7. m∠CBE + m∠DBF = m∠CBE + m∠EBF   7. transitive property

8. m∠DBF =  m∠EBF                        8. subtraction property

 

From the figure it is clear that both the angles m∠DBF and  m∠EBF are equal.

What is an angle?

Angle is a geometrical figure formed by two rays meeting at a point.

Given, a ray BF bisects ∠ABC.

Therefore, m∠ABF = m∠CBF                      

From the figure, it is clear that, m∠ABF = m∠ABD + m∠DBF

Similarly, from the figure, it is clear that, m∠CBF = m∠CBE + m∠EBF

Now, m∠ABF = m∠CBE + m∠DBF  ...(1)        (Given, m∠ABD = m∠CBE)

Here, m∠CBF = m∠CBE + m∠EBF   ...(2)      (From the figure)

m∠ABF = m∠CBF

Therefore, right hand side of equation(1) and equation(2) are equal.

Now, m∠CBE + m∠DBF = m∠CBE + m∠EBF

Hence, m∠DBF =  m∠EBF

Learn more about an angle here:

https://brainly.com/question/13255546

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Ver imagen RajarshiG