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If the angular bisector of an angle of a triangle bisects the opposite side , prove that the triangle is an isosceles triangle.

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2 Answers

6 votes

Answer:

this is your answer look it once.thank you.

If the angular bisector of an angle of a triangle bisects the opposite side , prove-example-1
User MelnikovI
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7 votes

Answer:

See Below.

Explanation:

Please refer to the attachment below.

In order to complete the proof, we create a new segment DE that extends from D and is equal to AD. The endpoint of DE will be connected to B.

Statements: Reasons:


1)\text{ } AD\text{ bisects } CB Given


2)\text{ } CD=DB Definition of Bisector


3)\text{ } AE=DE Given


4)\text{ } \angle ADC \cong \angle EDB Vertical Angles are Congruent


5)\text{ } \Delta ADC\cong \Delta EDB SAS Congruence


6)\text{ } \angle BED\cong \angle CAD CPCTC


7)\text{ } AD\text{ bisects } \angle A Given


8)\text{ } \angle CAD\cong \angle BAD Definition of Congruence


9)\text{ } \angle BED\cong\angle BAD Substitute


10)\text{ } BE=BA Isosceles Triangle Theorem


11) \text{ } BE=CA CPCTC


12)\text{ } CA=BA Substitute


13)\text{ } \Delta ABC\text{ is isosceles} Isosceles Triangle Definition

If the angular bisector of an angle of a triangle bisects the opposite side , prove-example-1
User Rami Ammoun
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5.0k points