thx

5. can't be proven (not enough information)
9. 5∠AED=180°(5-2)
∠AED=108°
∠BAE=∠ABC=∠EDC=∠BCD=∠AED=108°
∠AED+∠EDA+∠DAE=180°
∠EDA=∠DAE
∠DAE=36°
∠BAF+∠DAE=108°
∠BAF=72°
∠BFA=∠BAF=72°
∠BFA+∠BFD=180°
∠BFD=108°
∠EDA=∠DAE=36°
∠FDC=72°
∠BFA=∠BAF+∠FBA=180°
∠FBA=36°
∠CBF+∠FBA=∠ABC
∠CBF=72°
∵∠CBF=∠FDC=72°
∠BFD=∠BCD=108°
∴BCDF is a //gram
∵BF=BC
∴BCDF is a rhombus