a)Aria,patratului=L²=169cm²=>L=13
b)Aria,rombului=(d₁xd₂)/2
16d₁/2=96cm²=>8d₁=96=>d₁=12
Diag.se,injumatatesc,si,formeaza,triunghiuri,dreptunghice,in,care,acestea,sunt,catete,si,din,care,se,poate,afla,latura,rombului.
(d₁/2)²+(d₂/2)²=L²=>8²+6²=L²=>L²=64+36=>L²=100=>L=10cm
13.a)Se,duce,perpendiculara,din,C,pe,AB,si,notam,cu,M,piciorul,acesteia
In,tr.dr.CMB
sin45°=MB/BC=>√2/2=MB/10√2=>MB=10cm
=>AB(baza,mare)=24
Cu,t.Pit.,calculam,cateta,CM,care,este,si,inaltime
CM²+MB²=BC²
CM²+100=200=>CM²=100=>CM=10CM
Aria,trapez=(B+b)xh/2
Aria=(24+14)10/2=>Aria=38x5=>Aria=190cm²
c)Din,tr.dr.ACB(AC_l_BC-ipoteza),cu,t.Pit.aflam,baza,mare,AB
AB²=AC²+BC²=>AB²=28+36=>AB²=64=>AB=8cm
Ducem,perpendiculara,din,C,pe,AB,si,notam,cu,M,piciorul,acesteia
Segm.AM,il,calculam,cu,t.cat.in,tr.dr.ACB
CA²=AMxAB=>28=AMx8=>AM=7/2=CD(baza,mica)
MB=AB-AM=>MB=8-7/2=>MB=9/2
Cu,t.inaltimii,aflam,CM
CM²=7/2x9/2=>CM²=36/4=>CM²=9=>CM=3cm
Aria=(B+b)xh/2=>Aria=(8+7/2)x3/2=>Aria=17,25cm²
6)Aria,triunghi=bxh/2=12x5/2=>Aria=30cm²
Cam,atat,am,putut,eu:)
