Răspuns:
Explicație pas cu pas:
I-----2-----I-------------5--------------I
I------I-----I-----I-----I-----I-----I-----I
M C N
MC + CN = 14 cm
MC/CN = 2/5
MC = 2/5 x CN
MC = 2CN/5
2CN/5 + CN = 14 /x5
2CN + 5CN = 70
7CN = 70
CN = 70 : 7
CN = 10 cm
MC + 10 = 14
MC = 14 - 10
MC = 4 cm
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