Tolong pake caranya yaaa, terima kasihhh

AB = CB = EC = 12 cm
BD = DE = AE

perbandingan sdt 45° =
s : m = 1 : √2
AB : AC = 1 : √2
12/AC = 1/√2
AC = 12√2 cm

BD = AC - EC
BD = (12√2 - 12) cm
= ... hitung sendiri yaa