ABCD-trapez isoscel⇒AD=CB-LATURI NEPARALELE, AB=8cm, DC=6 cm, ung (ABC)=60 gr, ducem inaltimile trapezului respectiv DE si CF, ⇒AE=FB=1cm,
In tr FBC drept in F , ung (FBC)=60 gr ⇒ung (BCF)=30 gr, ⇒BC =2 cm, FC=√3cm
A trapez=(AB+DC)*FC/2=14*√3/2=7√3cm
A-aria trapez