Triangle Bisectors

This entry is part 31 of 71 in the series Durtles Problems of the Weeks
Problem of the Week #31: Monday August 7th, 2023
As before, these problems are the results of me following my curiosity, and I make no promises regarding the topics, difficulty, solvability of these problems.
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Let’s start with a right triangle with a height of 1 unit and consider two ways of dividing it into two triangles.  The first is to bisect the base, like this:

Right triangle with the right angle on the bottom left and a line connecting the top angle to the midpoint of the base.

The second is to bisect the angle opposite to the base, like this:

Right triangle with the right angle on the bottom left with a line bisecting the top angle and extending to meet the base.

Notice that in both of these cases, the dividing line intersects the base.

a). In which case is the point of intersection closer to the right angle?

b). If the base of the triangle is also 1 unit long, how far apart are these two intersection points?

c). Do the intersection points become closer or further apart as we increase the length of the base?

d). What is the maximum proportion of this difference compared to the whole base for all right triangles in this position that have a height of 1 unit?

e). Do the intersection points become closer or further apart as we decrease the measurement of the right angle (at the bottom left)?

f). What is the maximum proportion of this difference compared to the whole base for all triangles (not necessarily right triangles) in this position and have both a base and a height of 1 unit?

g). Share your own problem inspired by this one.

h). Give one of these questions to a friend/colleague/student/family member to start a mathematical discussion.

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