D) construction of the angle bisector.
So if you have a triangle that is not equilateral the perpendicular bisectors would not work so you need angle bisectors.
I have drawn a diagram
The green is the angle bisectors and the yellow the perpendicular bisectors.
You can see the problem straight away
So if you have a triangle that is not equilateral the perpendicular bisectors would not work so you need angle bisectors.
I have drawn a diagram
The green is the angle bisectors and the yellow the perpendicular bisectors.
You can see the problem straight away