Question

prove the result angle opp to equal sides of an iso triangles are equal

Answer 1

let ABC be an isosceles triangle and AD be the median,
then

we have two triangles,
∆ABD and ∆ACD,

now in ∆ABD and ∆ACD,

AB=AC (since ∆ is isosceles),
AD=AD (median),
BD=CD (since median bisect the side)
therefore by SSS congruence rule both the triangles are congruence,

hence

angle ABD = angle ACD (BY CPCT)

Answer 2

this is the answer.............