fie AM si BN inaltimile tr,isoscel a)DC=AB+DM+CN DM=CN ΔBNC este dreptunghic inM si m(MBC)=30 grade⇒BN=BC/2=2√2 cm conf T.Pitagora⇒CN²=BC²-BN²=32-8=24CN=√24=4√6 cm⇒DC=2√2+4√6+4√6=2√2+8√6 cmb)fiind isoscel diagonalele sunt egale AC=BD ΔBMD---DREPTUNGHIC IN M⇒BD²=DM²+C(N²BD²=(2√2+4√2)²+96=8+32+32+96=164 BD=√164=2√41 cm=AC