Răspunsuri

2014-08-25T19:13:07+03:00
Fie N mij. seg. DC.
AM=AD=DN=MN => NAMD romb=>
A{NAMD}= AN*DM/2
AM||NC;AM=NC=>AMCN\ paralelogram =>AN=CM
A{DANM}=A{MBCN}
 A{ABCD}=2  *AN*DM/2 =AN*DM=MC * DM