Take identical cut out of congruent triangle of sides 3cm,4cm,5cm. You get a trapeziums. (check it!)which are the parallel sides here? Should the non-parallel sides be equal?

Answer 1

Take identical cut
identical to what?

Do you mean to cut off each corner of the triangle? guess not.
what do you mean by "take a cut out of a triangle"?
Maybe you could describe things a bit. So,
Start with triangle ABC with sides a=3, b=4, c=5
then ...

Answer 2

Show the answer