Does Bisecting Angle A in a 3-4-5 Triangle Divide It into Two Equal Areas?

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The discussion centers on whether bisecting Angle A in a 3-4-5 right triangle (where AB = 4, BC = 3, and AC = 5) results in two triangles of equal area and whether the bisector intersects the midpoint of BC. It is established that the bisector does not necessarily cross the midpoint of BC. The Law of Sines is applicable for calculating the lengths of the segments formed by the bisector, specifically to find side BD after determining the angles involved.

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Given triangle ABC. And given that it’s a common 3-4-5 right triangle. (this still qualifies as a scalene)

So

AB = 4

BC = 3

AC = 5 is the hypotenuse

If Angle A was bisected, do the two newly formed triangles have the same area? And would the bisecting line hit the midpoint of BC?

Is there a triangle law that applies to this question? My inital thought is that the bisecting angle line doen't not necessaily cross the midpoint of BC. looking for a proof or any help.

Thanks!
 
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Aceterp said:
Given triangle ABC. And given that it’s a common 3-4-5 right triangle. (this still qualifies as a scalene)

So

AB = 4

BC = 3

AC = 5 is the hypotenuse

If Angle A was bisected, do the two newly formed triangles have the same area? And would the bisecting line hit the midpoint of BC?

Is there a triangle law that applies to this question? My inital thought is that the bisecting angle line doen't not necessaily cross the midpoint of BC. looking for a proof or any help.

Thanks!
Angle A = arctan(3/4), so the bisected angle is half of that. Let D be the point where the angle bisector hits BC. Since you know angle DAB, angle BDA is the complement of angle DAB. Now you know all three angles (angle ABC is a right angle), and one side (AB = 4), so you can use the Law of Sines to find the other side, BD. Hopefully you can take it from there.
 

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