onsider the following proof of the Base Angles Theorem. Which statement should fill in the blank?

PROOF: Given isosceles △ABC

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with AB¯¯¯¯¯¯¯¯≅BC¯¯¯¯¯¯¯¯
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¯

𝐵
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¯
, I can construct BD←→
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𝐷

, the angle bisector of ∠B

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. _____________________. I also know that line segments are congruent to themselves, so BD¯¯¯¯¯¯¯¯≅BD¯¯¯¯¯¯¯¯
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¯

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¯
by the reflexive property of congruence. I now have two pairs of sides and an included angle that are congruent, so I know that △ABD≅△CBD

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𝐷


𝐶
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by the SAS Congruence Theorem. Finally, corresponding parts of congruent triangles are congruent by the CPCTC Theorem, so ∠A≅∠C

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.

(1 point)
Responses

Then, by the definition of an angle bisector, I know that ∠BAC≅∠BCA

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𝐴
𝐶


𝐵
𝐶
𝐴
.
Then, by the definition of an angle bisector, I know that angle upper B upper A upper C congruent to angle upper B upper C upper A .

 Then, by the definition of a midpoint, I know that AD¯¯¯¯¯¯¯¯≅DC¯¯¯¯¯¯¯¯
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¯

𝐷
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¯
.
 Then, by the definition of a midpoint, I know that Modifying above upper A upper D with bar congruent to Modifying above upper D upper C with bar .

Then, by the definition of an isosceles triangle, I know that AB¯¯¯¯¯¯¯¯≅CA¯¯¯¯¯¯¯¯
𝐴
𝐵
¯

𝐶
𝐴
¯
.
Then, by the definition of an isosceles triangle, I know that Modifying above upper A upper B with bar congruent to Modifying above upper C upper A with bar .

Then, by the definition of an angle bisector, I know that ∠ABD≅∠CBD

𝐴
𝐵
𝐷


𝐶
𝐵
𝐷
.

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 hours ago

The appropriate statement to fill in the blank is:

Then, by the definition of an angle bisector, I know that ∠ABD≅∠CBD.

This choice confirms that angle BD bisects angle ABC, establishing that the two angles (∠ABD and ∠CBD) formed by the bisector are congruent before proceeding with the proof. It aligns with the given information and the logical progression of the proof that follows.