Question

FIE x y si z lungimele laturilor unui treptunghi aflati aceste lungimi daca
2x+y+z=71cm
x+2y+z=72cm
x+y+2z=73cm

Answer 1

2x+y+z=71 cm
x+2y+z=72 cm
x+y+2z=73 cm
___________
4x+4y+4z=71 cm+72 cm+73 cm
4(x+y+z) =216 cm
   x+y+z   =216 cm/4
   x+y+z   =  54 cm
2x+y+z=71 cm
x+54 cm=71 cm
x             =71 cm-54 cm
x             =17 cm

x+2y+z  =72 cm
54 cm+y=72 cm 
             y=72 cm-54 cm
             y=18 cm

x+y+2z  =73 cm
54 cm+z=73 cm
             z=73 cm-54 cm
             z=19 cm