B could be on the Thales circle over AC, and AB need not be equal to BC.
One method to check whether AB : BC is the same proportion as CD : DA
could be to draw a line between B and D. If the line crosses the line
AC in the middle, the proportion is the same. Otherwise not.
B could be on the Thales circle over AC, and AB need not be equal to BC.
One method to check whether AB : BC is the same proportion as CD : DA could be to draw a line between B and D. If the line crosses the line AC in the middle, the proportion is the same. Otherwise not.
Bye
See also: Thales theorem