Question

in the given figure if AD=BD=CD prove that angle BAC is a right angle

Answer 1

AD IS THE MEDIAN OF TRIANGLE BAC
$ar(bad) = ar(cad) \\ cad + bad = 180 \\ 2bad = 180 \\ bad = 90 \\ cab \: is \: right \: angled \: triangle$

Answer 2

BAC = 90°
And 90° = a right angle......