a. Δ echilateral aria = l²√3 /4 = ( 8√3)² ·√3 /4 =48√3 cm²
b.Δ drept aria = cat· cat /2 = AB·AC/2 =4√2· 6√2 /2 = 24 cm²
c. Δ drept isoscel AB=AC AB²+AB²=144·6 ; 2AB²=864 ; AB²= 432 =144·3
AB=AC= 12√3
aria= cat·cat/2= 12√3· 12√3 /2 =216 cm²
d.aria = AB·AC ·sin 150⁰ /2= 6,4·15·1/2 =96 / 2 =48 cm²