Răspuns :
Răspuns:
P romb=4l
P dreptunghi=2L+2l
l=L/3=57/3=19 cm
P dreptunghi=2×57+2×19=114+38=152 cm
P romb=152 cm
l romb=152÷4=38 cm
[tex]l = \frac{1}{3} \times 57 = \frac{57}{3} = 19[/tex]
[tex]P = 2 \times (57 + 19) = 2 \times 76 = 152[/tex]
[tex]P _{romb} = 152 = l _{romb} \times 4 [/tex]
[tex] l_{romb} = 152 \div 4 = 38[/tex]