1) AB=12cm
AC=150mm=15cm
BC=14dm=14cm
P=suma tuturor laturilor =14+15+12=41cm
2) L=120mm=12cm
P=2L+2l
34=2x12+2l
34=24+2l
34-24=2l
10=2l
l=5cm
3)l=27-8=19m
P= 2L+2l = 2x27+2x19 = 54+38=92m
Sper ca nu am facut vreo greseala din neatentie.Si cam asta e tema ta :)