am putea face cu 1/2|Δ|, dar e prea multde calcul...:)))
profitam ca AC||Ox, adioca (yA=yC)
deci avem o baza AC osorde calculat
AC=|xC-xA|=|3-1|=|2|=2
inal;timea din B, coresp lui AC, v a fi lunga de |yb-yC|=|yB-yA|=|-1-3|=|-4|=4
deci aria va fi
baza*inaltime /2=
4*2/2=4 unitatide arie
as simple as that!!!
