Explanation:
FD and BC are congruent
FD = 6.2
BC = 6.2
AC = AB + BC
AB and BC are congruent due to the three tick marks on both of them
AB = BC = 6.2
AC = 6.2 + 6.2
AC = 12.4
∠BDF = 26°
BD = hypotenuse, FD = 6.2
cos 26 = FD/BD
cos 26 = 6.2/BD
BD = 6.2/cos 26 = 6.2/0.8988 = 6.898
BD = 6.9
