Question

prove that a line segment have only one mid point

Answer 1

if possible let the line segment AB has two midpoints C and D
therefore AD=1 by 2 AB
AC=1 BY 2 AB
therefore AD-AC = 1 BY 2 AB -1 BY 2 AB
CD = O
Since CD=0 so C and D are some point
Every line segment has only one mid point

Answer 2

    let C and D be 2 mid points of line segment AB.
since C is the mid point , AC=CB=1/2 AB
similarily  AD=BD=1/2 AB
thus AC=AD
AD+CD=AD
therefore  CD=0 units  or C collides with D
hence every line segment has one and only one