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

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In a 3-4-5 right triangle, bisecting Angle A does not necessarily create two triangles of equal area, nor does the bisecting line necessarily intersect the midpoint of side BC. The bisector intersects side BC at point D, and the angles formed can be analyzed using the Law of Sines to determine the lengths of the segments created. The area of the two resulting triangles can be calculated to confirm whether they are equal. The discussion seeks a mathematical proof or further clarification on these properties.
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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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