Răspuns:
AB = AC = 150 cm; BC = 120 cm
Explicație pas cu pas:
[tex]AB = AC = x[/tex]
[tex]BC = \frac{4}{5} \times AC = \frac{4x}{5} [/tex]
[tex]P_{ΔABC} = 420 \: cm[/tex]
[tex]P_{ΔABC} = AB + AC + BC = x + x + \frac{4x}{5} = 2x + \frac{4x}{5} = \frac{14x}{5} [/tex]
[tex] = > \frac{14x}{5} = 420 \\ x = \frac{5 \times 420}{14} = > x = 150[/tex]
[tex]=> AB = AC = 150 \: cm \\ BC = \frac{4 \times 150}{5} = > BC = 120 \: cm[/tex]
