Question

If triangle is equilateral then it is isosceles first order logic

Answer 1

nane the triangle ABC

implies ab=bc=ac

then ab=bc
thus ang a=ang c
(angle opposite to en sides are equal)
eq1.......
bc=ac
thus ang b =ang c
(". ")
eq2.......
ab=ac
thus angb =ang a
(". ")
eq3......
from 1 ,2,3
ang a. = ang b.= Ang c
a+b+c=180(asp)
3a =180
a=60
thus a,b,c all are 60
hence proved