Question

Let ABCD be a convex quadrilateral such that |AB|+|BC|=√2|AC|,
|BC|+|DA|=√2|BD|
prove that ABCD is parallelogram.

Answer 1

\(|AB|+|BC|=\sqrt{2}|AC|\) or \(|AB|+|BC|=\sqrt{2|AC|}\) ?

Answer 2

first one i think ?

Answer 3

yea, it;s the first one