Am,desenat,triunghiul,ABC,cu,baza,BC,pe,orizontala.Unghiul,B,fiind,obtuz,am,construit,inaltimea,pe,prelungirea,BC.Am,notat,piciorul,inaltimii,cu,D.
m(∡ABD)=180°-135°=45°
=>ΔADB-dr.isoscel=>AD=BD=x
Cu,t.Pit.aflam,catetele
x²+x²=50
2x²=50=>x²=25=>x=5
Aria=bxh/2=6x5/2=15cm²
